Bump codecov/codecov-action from 1 to 2.1.0 (#163)

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 1 to 2.1.0.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/master/CHANGELOG.md)
- [Commits](codecov/codecov-action@v1...v2.1.0)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci_test.yml

@@ -58,7 +58,7 @@ jobs:
         run: |
           PYTORCH_TEST_WITH_SLOW=1 pytest ${{ matrix.unittest_type }}
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v1
+        uses: codecov/codecov-action@v2.1.0
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           file: ./coverage.xml