Bump julia-actions/cache from 1 to 2 (#522)

Bumps [julia-actions/cache](https://github.com/julia-actions/cache) from 1 to 2.
- [Release notes](https://github.com/julia-actions/cache/releases)
- [Changelog](https://github.com/julia-actions/cache/blob/main/devdocs/making_a_new_release.md)
- [Commits](julia-actions/cache@v1...v2)

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

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

Author: dependabot[bot]

.github/workflows/benchmark_pr.yml

@@ -15,7 +15,7 @@ jobs:
             - uses: julia-actions/setup-julia@v1
               with:
                 version: "1"
-            - uses: julia-actions/cache@v1
+            - uses: julia-actions/cache@v2
             - name: Extract Package Name from Project.toml
               id: extract-package-name
               run: |