Add Dependabot config for weekly npm updates

Author: ncw

.github/dependabot.yml

@@ -0,0 +1,18 @@
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 10
+    groups:
+      dev-dependencies:
+        dependency-type: "development"
+        update-types:
+          - "minor"
+          - "patch"
+      production-dependencies:
+        dependency-type: "production"
+        update-types:
+          - "minor"
+          - "patch"