Upgraded actions/cache from 3 to 4 (gantsign#209)

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v3...v4)

---
updated-dependencies:
- dependency-name: 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/ci.yml

@@ -26,14 +26,14 @@ jobs:
 
       - name: Tox cache
         id: tox-cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.cache/pip
           key: tox-${{ hashFiles('requirements/tox.txt') }}-py${{ steps.setup-python.outputs.python-version}}
 
       - name: Lint cache
         id: lint-cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .tox
           key: lint-${{ hashFiles('requirements/lint.txt') }}-py${{ steps.setup-python.outputs.python-version}}
@@ -84,14 +84,14 @@ jobs:
 
       - name: Tox cache
         id: tox-cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.cache/pip
           key: tox-${{ hashFiles('requirements/tox.txt') }}-py${{ steps.setup-python.outputs.python-version}}
 
       - name: Molecule cache
         id: molecule-cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .tox
           key: molecule-${{ hashFiles(format('requirements/ansible-{0}.txt', matrix.ansible-version)) }}-py${{ steps.setup-python.outputs.python-version}}