Update workflow

- Remove Python 5.5 and add Python 3.10
- Skip flake8 check

.github/workflows/pythonpackage.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.5, 3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9, 3.10]
 
     steps:
     - uses: actions/checkout@v2
@@ -23,13 +23,6 @@ jobs:
         pip install pytest-console-scripts
         pip install pytest-cov
         pip install coveralls
-    - name: Lint with flake8
-      run: |
-        pip install flake8
-        # stop the build if there are Python syntax errors or undefined names
-        flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
-        # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
-        flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
     - name: Test with pytest
       run: |
         pip install -e .