[devops] change dependabot schedule from daily to weekly and reduce PR limit from 10 to 5

Author: i4004

.github/dependabot.yml

@@ -1,10 +1,10 @@
 version: 2
 updates:
-- package-ecosystem: nuget
-  directory: "/"
-  schedule:
-    interval: daily
-    time: "06:45"
-    timezone: Asia/Dacca
-  open-pull-requests-limit: 10
-  target-branch: develop
+  - package-ecosystem: nuget
+    directory: "/"
+    schedule:
+      interval: weekly
+      time: "06:45"
+      timezone: Asia/Dacca
+    open-pull-requests-limit: 5
+    target-branch: develop