ci: move dependabot to monthly check

Author: niquerio

.github/dependabot.yml

@@ -4,9 +4,9 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "daily"
-      time: "15:00"
-      #day: "monday"
+      interval: "monthly"
+      time: "06:00"
+      day: "monday"
       timezone: "America/Detroit"
     commit-message:
       prefix: "fix: "