Bump actions/upload-artifact from 5.0.0 to 6.0.0 (#1846)

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 5.0.0 to 6.0.0.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v5.0.0...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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/tests.yml

@@ -84,15 +84,15 @@ jobs:
 
       - name: Upload coverage data
         if: always() && matrix.session == 'tests'
-        uses: actions/upload-artifact@v5.0.0
+        uses: actions/upload-artifact@v6.0.0
         with:
           name: coverage-data-${{ matrix.python-version }}-${{ matrix.os }}
           path: ".coverage.*"
           include-hidden-files: true
 
       - name: Upload documentation
         if: matrix.session == 'docs-build'
-        uses: actions/upload-artifact@v5.0.0
+        uses: actions/upload-artifact@v6.0.0
         with:
           name: docs
           path: docs/_build