Have dependabot update npm packages. NFC (#23713)

Author: sbc100

.github/dependabot.yml

@@ -5,7 +5,12 @@
 
 version: 2
 updates:
-  - package-ecosystem: "github-actions" # See documentation for possible values
+  - package-ecosystem: "npm"
+    directory: "/" # Look for `package.json` and `lock` files in the `root` directory
+    schedule:
+      interval: "weekly"
+
+  - package-ecosystem: "github-actions"
     directory: "/" # Location of package manifests
     schedule:
       interval: "weekly"