build: bump codecov/codecov-action from 1.0.13 to 2.1.0

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 1.0.13 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@v1.0.13...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] <support@github.com>

.github/workflows/build-test.yml

@@ -39,7 +39,7 @@ jobs:
     - name: Run test suite
       run: composer run-script test
 
-    - uses: codecov/codecov-action@v1.0.13
+    - uses: codecov/codecov-action@v2.1.0
       if: matrix.php-versions == '8.1'
       with:
         # Comma-separated list of files to upload