idea配置gradle国内镜像源

项目文件中找到build.gradle文件，修改其中的buildscript和allprojects地址：

buildscript {
    repositories {
        maven{ url 'http://maven.aliyun.com/nexus/content/groups/public/' }
        maven{ url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.0-alpha13'
    }
}
allprojects {
    repositories {
        maven{ url 'http://maven.aliyun.com/nexus/content/groups/public/'}
        maven{ url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
    }
}
task clean(type: Delete) {
    delete rootProject.buildDir
}