chore: fix typo in stalebot config

Author: balazsorban44

.github/workflows/stale.yml

@@ -22,4 +22,4 @@ jobs:
           days-before-pr-close: -1
           days-before-pr-stale: -1
           exempt-issue-labels: 'blocked,must,should,keep'
-          operation-per-run: 300 # 1 operation per 100 issues, the rest is to label/comment/close
+          operations-per-run: 300 # 1 operation per 100 issues, the rest is to label/comment/close