Merge pull request #421 from jGaboardi/master

update Codecov action: major version only

Author: jGaboardi

.github/workflows/unittests.yml

@@ -43,7 +43,7 @@
          if: matrix.os == 'windows-latest'
 
        - name: ${{ matrix.os }}, ${{ matrix.environment-file }}
-         uses: codecov/codecov-action@v1
+         uses: codecov/codecov-action@v2 
          with:
            token: ${{ secrets.CODECOV_TOKEN }}
            file: ./coverage.xml