[gha] update codecov push workflow to v2

Author: chrissimpkins

.github/workflows/py-coverage.yml

@@ -49,6 +49,6 @@ jobs:
           coverage report -m
           coverage xml
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v1
+        uses: codecov/codecov-action@v2
         with:
           file: ./coverage.xml