Reduce CRON frequency to once per month

Author: juntyr

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ on:
     branches:
       - '*'
   schedule:
-    - cron: '0 0 * * MON'
+    - cron: '0 0 1 * *'
 
 env:
   CARGO_TERM_COLOR: always

.github/workflows/security.yml

@@ -2,7 +2,7 @@ name: Security audit
 
 on:
   schedule:
-    - cron: '0 0 * * MON'
+    - cron: '0 0 1 * *'
 
 jobs:
   audit: