chore: upgrade gradle and android build plugin version to the latest

Author: Jacksgong

build.gradle

@@ -4,7 +4,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.0-alpha16'
+        classpath 'com.android.tools.build:gradle:3.3.0-alpha03'
         classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.7.3'
     }
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Thu May 17 22:09:35 CST 2018
+#Fri Aug 03 15:25:31 CST 2018
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.9-rc-1-all.zip