Update dispatch-matrix-test-on-comment.yml

Fixed

Author: jsinglet

.github/workflows/dispatch-matrix-test-on-comment.yml

@@ -38,6 +38,7 @@ jobs:
           client-payload: '{"pr": "${{ github.event.number  }}"}'
 
       - uses: actions/github-script@v6
+        if: ${{ github.event.issue.pull_request && contains(github.event.comment.body, '/test-matrix') }}
         with:
           script: |
             github.rest.issues.createComment({