> Cannot add task 'wrapper' as a task with that name already exists.

> Cannot add task 'wrapper' as a task with that name already exists. 說是在android/build.gradle 文件36行報錯

最終發現原因是gradle版本問題

// 舊版本是:
task wrapper(type:Wrapper) {
    //configuration
}

// 新版本是：
wrapper {
    //configuration
}

改完之後，再次執行./gradlew assembleRelease

成功了。