Bump actions/cache from 3.3.3 to 4.0.0

Bumps [actions/cache](https://github.com/actions/cache) from 3.3.3 to 4.0.0.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@e12d46a...13aacd8)

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

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/validations.yaml

@@ -37,7 +37,7 @@ jobs:
 
       - name: Restore test-fixture cache
         id: unit-fixture-cache
-        uses: actions/cache@e12d46a63a90f2fae62d114769bbf2a179198b5c #v3.3.3
+        uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2 #v4.0.0
         with:
           path: internal/git/test-fixtures/repos
           key: ${{ runner.os }}-unit-fixture-cache-${{ hashFiles( 'internal/git/test-fixtures/cache.fingerprint' ) }}