Merge pull request #133 from reinout/dependabot/github_actions/action…

…s/cache-4

chore(deps): bump actions/cache from 3 to 4

.github/workflows/testing.yml

@@ -20,7 +20,7 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
       - name: Cache packages
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.cache/pip
           key: ${{ runner.os }}-pip-${{ matrix.python-version }}-${{ hashFiles('requirements.txt') }}