Adding workflow dispatch (#34868)

diff --git a/.github/workflows/stale.yaml b/.github/workflows/stale.yaml
index 5437430..a9953e6 100644
--- a/.github/workflows/stale.yaml
+++ b/.github/workflows/stale.yaml
@@ -1,5 +1,6 @@
 name: "Process Stale Issues and PRs"
 on:
+    workflow_dispatch:
     schedule:
         - cron: "30 1 * * *"