Update setup-python action to v4

Author: homeworkprod

.github/workflows/test.yml

@@ -16,7 +16,7 @@ jobs:
       # Python needs to be setup before checkout to prevent files from being
       # left in the source tree. See setup-python/issues/106.
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}