google maven repo国内地址

android gradle plugin 3.x 预备的google maven repo国内地址 https://dl.google.com/dl/android/maven2/

repositories {
    maven {
        url 'https://maven.google.com'
        // Alternative URL is 'https://dl.google.com/dl/android/maven2/'
    }
}

https://developer.android.google.cn/studio/build/dependencies.html#google-maven