fix: namespace not specified

[Sh1n3zZ]

从 Android Gradle 插件（AGP） 7.0.0 开始，AGP要求在每个模块的 build.gradle 文件中明确定义 namespace 以代替之前在 AndroidManifest.xml 中定义的 package 属性

Starting with Android Gradle Plugin (AGP) 7.0.0, AGP requires that namespace be explicitly defined in each module's build.gradle file in place of the package attribute previously defined in AndroidManifest.xml