build(deps): bump libc from 0.2.167 to 0.2.168 (#42)

Bumps [libc](https://github.com/rust-lang/libc) from 0.2.167 to 0.2.168.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/rust-lang/libc/releases">libc's
releases</a>.</em></p>
<blockquote>
<h2>0.2.168</h2>
<h3>Added</h3>
<ul>
<li>Linux: Add new process flags (<a
href="https://redirect.github.com/rust-lang/libc/pull/4174">#4174</a>)</li>
<li>Linux: Make <code>IFA_*</code> constants available on all Linux
targets <a
href="https://redirect.github.com/rust-lang/libc/pull/4185">rust-lang/libc#4185</a></li>
<li>Linux: add <code>MAP_DROPPABLE</code> <a
href="https://redirect.github.com/rust-lang/libc/pull/4173">rust-lang/libc#4173</a></li>
<li>Solaris, Illumos: add <code>SIGRTMIN</code> and
<code>SIGRTMAX</code> <a
href="https://redirect.github.com/rust-lang/libc/pull/4171">rust-lang/libc#4171</a></li>
<li>Unix, Linux: adding POSIX <code>memccpy</code> and
<code>mempcpy</code> GNU extension &lt;<a
href="https://redirect.github.com/rust-lang/libc/pull/4186">rust-lang/libc#4186</a>.</li>
</ul>
<h3>Deprecated</h3>
<ul>
<li>FreeBSD: Deprecate the CAP_UNUSED* and CAP_ALL* constants (<a
href="https://redirect.github.com/rust-lang/libc/pull/4183">#4183</a>)</li>
</ul>
<h3>Fixed</h3>
<ul>
<li>Make the <code>Debug</code> implementation for unions opaque (<a
href="https://redirect.github.com/rust-lang/libc/pull/4176">#4176</a>)</li>
</ul>
<h3>Other</h3>
<ul>
<li>Allow the <code>unpredictable_function_pointer_comparisons</code>
lint where needed <a
href="https://redirect.github.com/rust-lang/libc/pull/4177">rust-lang/libc#4177</a></li>
<li>CI: Upload artifacts created by libc-test <a
href="https://redirect.github.com/rust-lang/libc/pull/4180">rust-lang/libc#4180</a></li>
<li>CI: Use workflow commands to group output by target <a
href="https://redirect.github.com/rust-lang/libc/pull/4179">rust-lang/libc#4179</a></li>
<li>CI: add caching <a
href="https://redirect.github.com/rust-lang/libc/pull/4183">rust-lang/libc#4183</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/rust-lang/libc/blob/0.2.168/CHANGELOG.md">libc's
changelog</a>.</em></p>
<blockquote>
<h2><a
href="https://github.com/rust-lang/libc/compare/0.2.167...0.2.168">0.2.168</a>
- 2024-12-09</h2>
<h3>Added</h3>
<ul>
<li>Linux: Add new process flags (<a
href="https://redirect.github.com/rust-lang/libc/pull/4174">#4174</a>)</li>
<li>Linux: Make <code>IFA_*</code> constants available on all Linux
targets <a
href="https://redirect.github.com/rust-lang/libc/pull/4185">rust-lang/libc#4185</a></li>
<li>Linux: add <code>MAP_DROPPABLE</code> <a
href="https://redirect.github.com/rust-lang/libc/pull/4173">rust-lang/libc#4173</a></li>
<li>Solaris, Illumos: add <code>SIGRTMIN</code> and
<code>SIGRTMAX</code> <a
href="https://redirect.github.com/rust-lang/libc/pull/4171">rust-lang/libc#4171</a></li>
<li>Unix, Linux: adding POSIX <code>memccpy</code> and
<code>mempcpy</code> GNU extension &lt;<a
href="https://redirect.github.com/rust-lang/libc/pull/4186">rust-lang/libc#4186</a>.</li>
</ul>
<h3>Deprecated</h3>
<ul>
<li>FreeBSD: Deprecate the CAP_UNUSED* and CAP_ALL* constants (<a
href="https://redirect.github.com/rust-lang/libc/pull/4183">#4183</a>)</li>
</ul>
<h3>Fixed</h3>
<ul>
<li>Make the <code>Debug</code> implementation for unions opaque (<a
href="https://redirect.github.com/rust-lang/libc/pull/4176">#4176</a>)</li>
</ul>
<h3>Other</h3>
<ul>
<li>Allow the <code>unpredictable_function_pointer_comparisons</code>
lint where needed <a
href="https://redirect.github.com/rust-lang/libc/pull/4177">rust-lang/libc#4177</a></li>
<li>CI: Upload artifacts created by libc-test <a
href="https://redirect.github.com/rust-lang/libc/pull/4180">rust-lang/libc#4180</a></li>
<li>CI: Use workflow commands to group output by target <a
href="https://redirect.github.com/rust-lang/libc/pull/4179">rust-lang/libc#4179</a></li>
<li>CI: add caching <a
href="https://redirect.github.com/rust-lang/libc/pull/4183">rust-lang/libc#4183</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/rust-lang/libc/commit/e6082ef26096154e08ab0cb094d66d5ca116ee15"><code>e6082ef</code></a>
chore: release v0.2.168</li>
<li><a
href="https://github.com/rust-lang/libc/commit/26b53370967f23d8d43a11eb4ac6d4711b99ab1a"><code>26b5337</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-lang/libc/issues/4190">#4190</a>
from tgross35/backport-ci-artifacts</li>
<li><a
href="https://github.com/rust-lang/libc/commit/4344e542bae5662feb9e54cb51fb654ecf3ba5d8"><code>4344e54</code></a>
ci: Upload artifacts created by libc-test</li>
<li><a
href="https://github.com/rust-lang/libc/commit/abe73ab0f67bee4d5196c4a323b4663d2e3c7705"><code>abe73ab</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-lang/libc/issues/4187">#4187</a>
from tgross35/backport-romanesco</li>
<li><a
href="https://github.com/rust-lang/libc/commit/1e2da75bad39c606cb343ccfe7422a758036e5c5"><code>1e2da75</code></a>
adding POSIX memccpy and mempcpy GNU extension.</li>
<li><a
href="https://github.com/rust-lang/libc/commit/7457aa18e15860ff5d5448465dbad15f7438814a"><code>7457aa1</code></a>
fix: make Debug impl for unions opaque</li>
<li><a
href="https://github.com/rust-lang/libc/commit/8592ff9492319ae6a005c3d44119c815eb5d229a"><code>8592ff9</code></a>
Lift IFA_* constants from linux/gnu to linux</li>
<li><a
href="https://github.com/rust-lang/libc/commit/069c923305f648a117987062b11b957e9e8a6601"><code>069c923</code></a>
Test(semver/linux): Add missing PF_* constants</li>
<li><a
href="https://github.com/rust-lang/libc/commit/05768aacb774fcda08b59eecd19bb56736a17b8b"><code>05768aa</code></a>
Docs(linux): Add docs for <code>PF_*</code> constants</li>
<li><a
href="https://github.com/rust-lang/libc/commit/0e89233900e524347c810287ff8f1bb03bdb0e9a"><code>0e89233</code></a>
Feat(linux): Add new process flags</li>
<li>Additional commits viewable in <a
href="https://github.com/rust-lang/libc/compare/0.2.167...0.2.168">compare
view</a></li>
</ul>
</details>
<br />


[![Dependabot compatibility
score](https://dependabot-badges.githubapp.com/badges/compatibility_score?dependency-name=libc&package-manager=cargo&previous-version=0.2.167&new-version=0.2.168)](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)

Dependabot will resolve any conflicts with this PR as long as you don't
alter it yourself. You can also trigger a rebase manually by commenting
`@dependabot rebase`.

[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)

---

<details>
<summary>Dependabot commands and options</summary>
<br />

You can trigger Dependabot actions by commenting on this PR:
- `@dependabot rebase` will rebase this PR
- `@dependabot recreate` will recreate this PR, overwriting any edits
that have been made to it
- `@dependabot merge` will merge this PR after your CI passes on it
- `@dependabot squash and merge` will squash and merge this PR after
your CI passes on it
- `@dependabot cancel merge` will cancel a previously requested merge
and block automerging
- `@dependabot reopen` will reopen this PR if it is closed
- `@dependabot close` will close this PR and stop Dependabot recreating
it. You can achieve the same result by closing it manually
- `@dependabot show <dependency name> ignore conditions` will show all
of the ignore conditions of the specified dependency
- `@dependabot ignore this major version` will close this PR and stop
Dependabot creating any more for this major version (unless you reopen
the PR or upgrade to it yourself)
- `@dependabot ignore this minor version` will close this PR and stop
Dependabot creating any more for this minor version (unless you reopen
the PR or upgrade to it yourself)
- `@dependabot ignore this dependency` will close this PR and stop
Dependabot creating any more for this dependency (unless you reopen the
PR or upgrade to it yourself)


</details>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>