pin pip version to run github workflows

.github/workflows/test-package.yml

@@ -50,7 +50,7 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
       run: |
-        python -m pip install --upgrade pip
+        python -m pip install pip==21.0.1
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
     - name: Run mysql
       env: