docs: make sure that only the main branch of the main repo will deplo…

…y pages (#666)

.github/workflows/docs.yml

@@ -24,5 +24,5 @@ jobs:
       - name: Build site
         run: mkdocs build
       - name: Deploy to gh-pages
-        if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main' && github.repository == 'mindspore-lab/mindcv'
         run: mkdocs gh-deploy --force