update ci-testing.yml with on: cron (#572)

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

.github/workflows/stale.yml

@@ -1,17 +1,17 @@
 name: Close stale issues
 on:
   schedule:
-  - cron: "0 0 * * *"
+    - cron: "0 0 * * *"
 
 jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/stale@v1
-      with:
-        repo-token: ${{ secrets.GITHUB_TOKEN }}
-        stale-issue-message: 'This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
-        stale-pr-message: 'This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
-        days-before-stale: 30
-        days-before-close: 5
-        exempt-issue-label: 'documentation,tutorial'
+      - uses: actions/stale@v1
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          stale-issue-message: 'This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
+          stale-pr-message: 'This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
+          days-before-stale: 30
+          days-before-close: 5
+          exempt-issue-label: 'documentation,tutorial'