Bump actions/cache from 4 to 5

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -66,7 +66,7 @@ jobs:
           echo "::set-output name=dir::$(pip cache dir)"
 
       - name: Cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: ${{ steps.pip-cache.outputs.dir }}
           key: pip-test-python-${{ matrix.python-version }}-django-${{ matrix.django-version }}-redis-${{ matrix.redis-version }}-${{ hashFiles('**/setup.*') }}
@@ -124,7 +124,7 @@ jobs:
           echo "::set-output name=dir::$(pip cache dir)"
 
       - name: Cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: ${{ steps.pip-cache.outputs.dir }}
           key: pip-lint-${{ hashFiles('**/setup.*') }}
@@ -165,7 +165,7 @@ jobs:
           echo "::set-output name=dir::$(pip cache dir)"
 
       - name: Cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: ${{ steps.pip-cache.outputs.dir }}
           key: pip-check-changelog-${{ hashFiles('**/setup.*') }}