ci: bump actions/upload-pages-artifact from 3.0.1 to 4.0.0

Bumps [actions/upload-pages-artifact](https://github.com/actions/upload-pages-artifact) from 3.0.1 to 4.0.0.
- [Release notes](https://github.com/actions/upload-pages-artifact/releases)
- [Commits](actions/upload-pages-artifact@56afc60...7b1f4a7)

---
updated-dependencies:
- dependency-name: actions/upload-pages-artifact
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/docs.yml

@@ -30,7 +30,7 @@ jobs:
 
       - run: mkdocs build --strict
 
-      - uses: actions/upload-pages-artifact@56afc609e74202658d3ffba0e8f6dda462b719fa # v3.0.1
+      - uses: actions/upload-pages-artifact@7b1f4a764d45c48632c6b24a0339c27f5614fb0b # v4.0.0
         with:
           path: site