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

.github/workflows/ci-testing.yml

@@ -45,7 +45,7 @@ jobs:
       run: echo "dir=$(pip cache dir)" >> $GITHUB_OUTPUT
 
     - name: Cache pip
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ${{ steps.pip-cache.outputs.dir }}
         key: ${{ runner.os }}-${{ matrix.python-version }}-${{ matrix.requires }}-pip-${{ hashFiles('requirements.txt') }}

.github/workflows/docs-deploy.yml

@@ -22,7 +22,7 @@ jobs:
     # Note: This uses an internal pip API and may not always work
     # https://github.com/actions/cache/blob/master/examples.md#multiple-oss-in-a-workflow
     - name: Cache pip
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ~/.cache/pip
         key: pip-${{ hashFiles('requirements.txt') }}