Removing python 3.5 for tests

Author: HardNorth

.github/workflows/tests.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [2.7, 3.6, 3.7, 3.8, 3.9, 3.10]
+        python-version: ['2.7', '3.6', '3.7', '3.8', '3.9', '3.10']
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}