Check if @pyrobench is in comment body before firing action (#3474)

.github/workflows/pyrobench.yaml

@@ -3,7 +3,7 @@ on: issue_comment
 jobs:
   pyrobench:
     name: Run Pyrobench on demand by PR comment
-    if: ${{ github.event.issue.pull_request }}
+    if: ${{ (github.event.issue.pull_request) && contains('@pyrobench', github.event.comment.body) }}
     runs-on: ubuntu-latest
     steps:
       - uses: actions/setup-go@v5