Bump codecov/codecov-action from 5 to 6 in the github-actions group (#270)

Bumps the github-actions group with 1 update: [codecov/codecov-action](https://github.com/codecov/codecov-action).


Updates `codecov/codecov-action` from 5 to 6
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@v5...v6)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
...

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

Author: dependabot[bot]

.github/workflows/build-test.yml

@@ -136,7 +136,7 @@ jobs:
         path: ${{ steps.dotnet-test.outputs.test-results-dir }}
     - name: Upload test coverage to Codecov
       if: matrix.os == 'ubuntu-latest'
-      uses: codecov/codecov-action@v5
+      uses: codecov/codecov-action@v6
       with:
         token: ${{ secrets.CODECOV_TOKEN }} # even though it's not required for public repos it helps with intermittent failures caused by https://community.codecov.com/t/upload-issues-unable-to-locate-build-via-github-actions-api/3954, https://github.com/codecov/codecov-action/issues/598
         files: ${{ steps.dotnet-test.outputs.test-coverage-file }}