Stale github.actor bug fix (#3483)

Author: glenn-jocher

.github/workflows/stale.yml

@@ -11,7 +11,7 @@ jobs:
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           stale-issue-message: |
-            👋 Hello @${{ github.actor }}, this issue has been automatically marked as stale because it has not had recent activity. Please note it will be closed if no further activity occurs.
+            👋 Hello, this issue has been automatically marked as stale because it has not had recent activity. Please note it will be closed if no further activity occurs.
 
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