Reduce codeql-analysis workflow frequency.

Author: fabiocaccamo

.github/workflows/codeql-analysis.yml

@@ -15,10 +15,9 @@ on:
   push:
     branches: [ main ]
   pull_request:
-    # The branches below must be a subset of the branches above
     branches: [ main ]
   schedule:
-    - cron: '15 21 * * 3'
+    - cron: "0 0 1 * *"
 
 jobs:
   analyze: