fix workflow

Author: Clare72

.github/workflows/performance-test.yml

@@ -238,4 +238,4 @@ jobs:
         uses: ad-m/github-push-action@master
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          branch: ${{ github.ref }}
+          branch: ${{ github.head_ref || github.ref_name }}