try new pip install for codecov

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install codecov
+          pip install coverage
           pip install -r requirements.txt
       - name: Run tests with unittest and codecov
         run: coverage run -m unittest discover tests -b