Bump julia-actions/setup-julia from 2.5.0 to 2.6.0 (#295)

Bumps [julia-actions/setup-julia](https://github.com/julia-actions/setup-julia) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/julia-actions/setup-julia/releases)
- [Changelog](https://github.com/julia-actions/setup-julia/blob/master/devdocs/making_a_new_release.md)
- [Commits](a0a0978...9b79636)

---
updated-dependencies:
- dependency-name: julia-actions/setup-julia
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/pr_checks.yml

@@ -71,7 +71,7 @@ jobs:
       ### Clean (not cleanall!):
       - run: make clean
       ### Make sure there are no uncommited changes
-      - uses: julia-actions/setup-julia@a0a0978e28861c11a3490cee468f87d5b568851a # v2.5.0
+      - uses: julia-actions/setup-julia@9b79636afcfb07ab02c256cede01fe2db6ba808c # v2.6.0
         with:
           version: '1'
       - run: git --no-pager status
@@ -214,7 +214,7 @@ jobs:
       # - run: npm install --package-lock-only
       - run: npm install
       ### Make sure there are no uncommited changes
-      - uses: julia-actions/setup-julia@a0a0978e28861c11a3490cee468f87d5b568851a # v2.5.0
+      - uses: julia-actions/setup-julia@9b79636afcfb07ab02c256cede01fe2db6ba808c # v2.6.0
         with:
           version: '1'
       - run: git --no-pager status