Bump actions/upload-artifact from 4.6.1 to 6.0.0

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4.6.1 to 6.0.0.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v4.6.1...v6.0.0)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/tests.yml

@@ -70,7 +70,7 @@ jobs:
         run: nox --force-color -s security
 
       - name: Upload coverage data
-        uses: actions/upload-artifact@v4.6.1
+        uses: actions/upload-artifact@v6.0.0
         with:
           name: ${{ matrix.os }}-${{ matrix.python-version }}.coverage-data
           path: ".coverage.*"