chore: Bump codecov/codecov-action from 5 to 6 (#635)

Bumps
[codecov/codecov-action](https://github.com/codecov/codecov-action) from
5 to 6.

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/checks.yml

@@ -60,7 +60,7 @@ jobs:
           PYTEST_TORCH_DTYPE: ${{ matrix.dtype || 'float32' }}
 
       - name: Upload results to Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           token: ${{ secrets.CODECOV_TOKEN }}