Update pylint.yml

.github/workflows/pylint.yml

@@ -7,10 +7,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - name: Set up Python 3.10
+    - name: Set up Python 3.9
       uses: actions/setup-python@v1
       with:
-        python-version: '3.10'
+        python-version: '3.9'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip