Update ci.yml

Author: jpdakran

Diff for: .github/workflows/ci.yml

@@ -14,12 +14,12 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
-        python: ['3.6', '3.7']
+        python: ['3.6', '3.7', '3.8', '3.9']
     steps:
     - uses: actions/checkout@v2
     - uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python }}
-    - run: python -mpip install --upgrade setuptools pip tox virtualenv
+    - run: python -m pip install --upgrade setuptools pip tox virtualenv
     - run: tox -e py
     - run: tox -e mypy