Bump codecov/codecov-action from 4 to 5

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 4 to 5.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@v4...v5)

---
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/tests-unit.yml

@@ -27,4 +27,4 @@ jobs:
           time env PYTHONPATH=. pytest -v --cov=chewie test/unit/test_*.py
       - if: ${{ matrix.python-version == env.CODECOV_PY_VER }}
         name: Upload codecov
-        uses: codecov/codecov-action@v4
+        uses: codecov/codecov-action@v5