Bumped versions in Github actions configuration to v3.

.github/workflows/main.yml

@@ -21,18 +21,13 @@ jobs:
         - '3.10'
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
 
-    - uses: actions/setup-python@v2
+    - uses: actions/setup-python@v3
       with:
         python-version: ${{ matrix.python-version }}
-
-    - uses: actions/cache@v2
-      with:
-        path: ~/.cache/pip
-        key: ${{ runner.os }}-pip-${{ hashFiles('requirements/*.txt') }}
-        restore-keys: |
-          ${{ runner.os }}-pip-
+        cache: 'pip'
+        cache-dependency-path: 'requirements/*.txt'
 
     - name: Upgrade packaging tools
       run: python -m pip install --upgrade pip setuptools virtualenv wheel