Update Dependabot schedule to weekly

Author: zhongkechen

.github/dependabot.yml

@@ -3,9 +3,8 @@ updates:
   - package-ecosystem: "maven"
     directory: "/"
     schedule:
-      interval: "daily"
-      time: "09:00"
-      timezone: "UTC"
+      interval: "weekly"
+      day: "monday"
     open-pull-requests-limit: 5
     commit-message:
       prefix: "[maven]"
@@ -16,9 +15,8 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/.github/workflows"
     schedule:
-      interval: "daily"
-      time: "09:00"
-      timezone: "UTC"
+      interval: "weekly"
+      day: "monday"
     open-pull-requests-limit: 5
     commit-message:
       prefix: "[github-actions]"