Revert: "chore(deps): Bump aws-actions/stale-issue-cleanup from 5 to 6" (#23024)

Reverts #23008

v6 is broken and was not ready for prod. It must have been accidentally released.

https://github.com/aws-actions/stale-issue-cleanup/tree/v6

TT: V771397092

Author: ryparker

Diff for: .github/workflows/close-stale-issues.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Stale issue job
     steps:
-    - uses: aws-actions/stale-issue-cleanup@v6
+    - uses: aws-actions/stale-issue-cleanup@v5
       with:
         # Setting messages to an empty string will cause the automation to skip
         # that category