⬆️ Bump actions/cache from 2 to 4

Bumps [actions/cache](https://github.com/actions/cache) from 2 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v2...v4)

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

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

Author: dependabot[bot]

.github/workflows/run-project-tests.yml

@@ -40,7 +40,7 @@ jobs:
               run: echo "::set-output name=dir::$(pip cache dir)"
 
             - name: Cache dependencies
-              uses: actions/cache@v2
+              uses: actions/cache@v4
               with:
                   path: ${{ steps.pip-cache.outputs.dir }}
                   key:

.github/workflows/run-tests.yml

@@ -35,7 +35,7 @@ jobs:
               run: echo "::set-output name=dir::$(pip cache dir)"
 
             - name: Cache dependencies
-              uses: actions/cache@v2
+              uses: actions/cache@v4
               with:
                   path: ${{ steps.pip-cache.outputs.dir }}
                   key: