Fix workflow

.github/workflows/pythonpackage.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10]
+        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
 
     steps:
     - uses: actions/checkout@v2
@@ -19,6 +19,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
+        pip install wheel
         pip install pytest
         pip install pytest-console-scripts
         pip install pytest-cov