Add dependabot configuration to monitor Gradle plugins

.github/dependabot.yml

@@ -0,0 +1,17 @@
+version: 2
+registries:
+  gradle-plugin-portal:
+    type: maven-repository
+    url: https://plugins.gradle.org/m2
+    username: dummy # Required by dependabot
+    password: dummy # Required by dependabot
+updates:
+  - package-ecosystem: "gradle"
+    directory: "/"
+    allow:
+      - dependency-name: "com.gradle*"
+    registries:
+      - gradle-plugin-portal
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 10