Update dependabot.yml for aws

Author: vlbee

.github/dependabot.yml

@@ -1,11 +1,26 @@
 version: 2
 updates:
+  - package-ecosystem: npm
+    directory: /cdk
+    schedule:
+      interval: "monthly"
+    # The version of AWS CDK libraries must match those from @guardian/cdk.
+    ignore:
+      - dependency-name: "aws-cdk"
+      - dependency-name: "aws-cdk-lib"
+      - dependency-name: "constructs"
+      
   - package-ecosystem: npm
     directory: /notificationworkerlambda/cdk
     schedule:
-      interval: daily
+      interval: "monthly"
+    # The version of AWS CDK libraries must match those from @guardian/cdk.
+    ignore:
+      - dependency-name: "aws-cdk"
+      - dependency-name: "aws-cdk-lib"
+      - dependency-name: "constructs"
 
   - package-ecosystem: github-actions
     directory: /
     schedule:
-      interval: daily
+      interval: weekly