fix daily scan (#499)

*Issue #, if available:*

*Description of changes:*
fix daily scan schedule run rate to every 6 hours as expected: `cron: '0
*/6 * * *'`

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Author: ezhang6811

.github/workflows/daily-scan.yml

@@ -9,7 +9,7 @@ name: Daily scan
 
 on:
   schedule: # scheduled to run every 6 hours
-    - cron: '20 */6 * * **' #  “At minute 20 past every 6th hour.” 
+    - cron: '20 */6 * * *' #  “At minute 20 past every 6th hour.”
   workflow_dispatch: # be able to run the workflow on demand
 
 env: