Add error handling for Go submodule tag creation

Co-authored-by: friggeri <106686+friggeri@users.noreply.github.com>

Author: Copilot

.github/workflows/publish.yml

@@ -209,7 +209,13 @@ jobs:
         run: |
           git config user.name "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
-          git tag "go/v${{ needs.version.outputs.version }}"
-          git push origin "go/v${{ needs.version.outputs.version }}"
+          TAG_NAME="go/v${{ needs.version.outputs.version }}"
+          if git rev-parse "$TAG_NAME" >/dev/null 2>&1; then
+            echo "Tag $TAG_NAME already exists, skipping"
+          else
+            git tag "$TAG_NAME"
+            git push origin "$TAG_NAME"
+            echo "Created and pushed tag $TAG_NAME"
+          fi
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}