Bump julia-actions/setup-julia from 2.5.0 to 2.6.0

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](julia-actions/setup-julia@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] <[email protected]>

.github/workflows/CI.yml

@@ -49,7 +49,7 @@ jobs:
         with:
           persist-credentials: false
 
-      - uses: julia-actions/setup-julia@a0a0978e28861c11a3490cee468f87d5b568851a # v2.5.0
+      - uses: julia-actions/setup-julia@9b79636afcfb07ab02c256cede01fe2db6ba808c # v2.6.0
         with:
           version: ${{ matrix.version }}