Bump bundler-audit from bc041d1 to d8af649 (#526)

Bumps [bundler-audit](https://github.com/rubysec/bundler-audit) from `bc041d1` to `d8af649`.
- [Commits](rubysec/bundler-audit@bc041d1...d8af649)

---
updated-dependencies:
- dependency-name: bundler-audit
  dependency-type: direct:development
...

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

Gemfile.lock

@@ -1,6 +1,6 @@
 GIT
   remote: https://github.com/rubysec/bundler-audit.git
-  revision: bc041d13eeccab70dd01672c097e8906108d07e3
+  revision: d8af649e9bb7552b25e46e4de2aa0828e0b3076e
   specs:
     bundler-audit (0.9.1)
       bundler (>= 1.2.0, < 3)