Make react-native depend on react-native-gradle-plugin

Summary:
Similarly to what we did for react-native-codegen, I'm introducing
a dependency between RN and the Gradle plugin, to be processed upon OSS bumps.

Changelog:
[General] [Added] - Make react-native depend on react-native-gradle-plugin

Reviewed By: motiz88

Differential Revision: D31334773

fbshipit-source-id: 978da4946b7864d891553e6a7dcb67783399e76f

package.json

@@ -108,6 +108,7 @@
     "pretty-format": "^26.5.2",
     "promise": "^8.0.3",
     "react-devtools-core": "^4.23.0",
+    "react-native-gradle-plugin": "^0.0.4",
     "react-refresh": "^0.4.0",
     "react-shallow-renderer": "16.14.1",
     "regenerator-runtime": "^0.13.2",