chore(deps): pin actions/stale action to 5bef64f (#6295)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/stale](https://redirect.github.com/actions/stale) | action |
pinDigest | -> `5bef64f` |

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.github/workflows/close-stale.yml

@@ -11,7 +11,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v9
+      - uses: actions/stale@5bef64f19d7facfb25b37b414482c7164d639639 # v9
         with:
           stale-pr-message: 'This PR was marked stale due to lack of activity. It will be closed in 14 days.'
           close-pr-message: 'Closed as inactive. Feel free to reopen if this PR is still being worked on.'