Update dependabot.yml

- Add maven.google.com to the custom registries

Author: warnyul

.github/dependabot.yml

@@ -4,8 +4,16 @@
 # https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
 
 version: 2
+registries:
+  maven-google:
+    type: maven-repository
+    url: https://maven.google.com
+    username: ""
+    password: ""
 updates:
   - package-ecosystem: "gradle"
     directory: "/"
+    registries:
+      - maven-google
     schedule:
       interval: "daily"