Add dependabot config (actions#1688)

* Add dependabot config
* Group minor and patch updates for NPM and GH Actions

.github/dependabot.yml

@@ -0,0 +1,20 @@
+---
+version: 2
+
+updates:
+- package-ecosystem: "npm"
+  directory: "/"
+  schedule:
+    interval: "weekly"
+  groups:
+    minor-npm-dependencies:
+      # NPM: Only group minor and patch updates (we want to carefully review major updates)
+      update-types: [minor, patch]
+- package-ecosystem: "github-actions"
+  directory: "/"
+  schedule:
+    interval: "weekly"
+  groups:
+    minor-actions-dependencies:
+      # GitHub Actions: Only group minor and patch updates (we want to carefully review major updates)
+      update-types: [minor, patch]