Bump codecov/codecov-action from 5.5.2 to 6.0.0

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 5.5.2 to 6.0.0.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@671740a...57e3a13)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/tests.yaml

@@ -62,7 +62,7 @@ jobs:
         run: tox --skip-missing-interpreters=true
 
       - name: Upload coverage reports to Codecov
-        uses: codecov/codecov-action@671740ac38dd9b0130fbe1cec585b89eea48d3de # v5.5.2
+        uses: codecov/codecov-action@57e3a136b779b570ffcdbf80b3bdc90e7fab3de2 # v6.0.0
         if: ${{ !cancelled() }}
         with:
           token: ${{ secrets.CODECOV_TOKEN }}