fix: add GITHUB_TOKEN environment variable for frontend deployment trigger

.github/workflows/deploy_backend.yml

@@ -39,5 +39,11 @@ jobs:
           git add config.json
           git commit -m "Update deployed contract address" || echo "No changes to commit"
           git push
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Trigger frontend deployment
+        run: |
+          gh workflow run deploy_frontend.yml -r main
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}