Bump Android SDK to 28, Build Tools to 28.0.2, Gradle to 4.7, Gradle …

…Plugin to 3.2.0 (#21632)

Summary:
This PR is bumping compileSdkVersion to 28, buildToolsVersion to 28.0.2, Gradle to 4.7, Android Gradle plugin to 3.2.0.

Gradle 4.7 added support for Java 10 and 11.

allow-large-files

Release Notes:
--------------
[ANDROID] [ENHANCEMENT] [SDK] - bump to 28

Pull Request resolved: facebook/react-native#21632

Reviewed By: mdvacca

Differential Revision: D13084836

Pulled By: hramos

fbshipit-source-id: e0f493881e80e87faf8c3ef1ac77044495966a49

android/app/build.gradle

@@ -91,8 +91,8 @@ def enableSeparateBuildPerCPUArchitecture = true
 def enableProguardInReleaseBuilds = true
 
 android {
-    compileSdkVersion 27
-    buildToolsVersion "27.0.3"
+    compileSdkVersion 28
+    buildToolsVersion "28.0.2"
 
     defaultConfig {
         applicationId "com.facebook.react.uiapp"