Bump peaceiris/actions-gh-pages from 3 to 4 (#1530)

Author: dependabot[bot]

.github/workflows/build.yml

@@ -302,7 +302,7 @@ jobs:
         dotnet nuget push "$env:GITHUB_WORKSPACE/packages/*.nupkg" --api-key "$env:GITHUB_TOKEN" --source 'github'
     - name: Publish documentation
       if: github.event_name == 'push' && github.ref == 'refs/heads/master'
-      uses: peaceiris/actions-gh-pages@v3
+      uses: peaceiris/actions-gh-pages@v4
       with:
         github_token: ${{ secrets.GITHUB_TOKEN }}
         publish_branch: gh-pages