chore(deps): bump actions/upload-pages-artifact from 1 to 2

Bumps [actions/upload-pages-artifact](https://github.com/actions/upload-pages-artifact) from 1 to 2.
- [Release notes](https://github.com/actions/upload-pages-artifact/releases)
- [Commits](actions/upload-pages-artifact@v1...v2)

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

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/site.ci.yml

@@ -240,7 +240,7 @@ jobs:
           name: site-tarball-phase2
           path: ./site.tar.gz
       - name: "Upload: Site Artifact"
-        uses: actions/upload-pages-artifact@v1
+        uses: actions/upload-pages-artifact@v2
         with:
           path: build/site