Remove unnecessary extensions from `hello-android` sample
Remove unnecessary extensions from `hello-android` sample

See #155

robinverduijn/gradle,gradle/gradle,robinverduijn/gradle,blindpirate/gradle,gradle/gradle-script-kotlin,robinverduijn/gradle,robinverduijn/gradle,robinverduijn/gradle,blindpirate/gradle,blindpirate/gradle,robinverduijn/gradle,robinverduijn/gradle,robinverduijn/gradle,gradle/gradle,gradle/gradle,gradle/gradle,robinverduijn/gradle,gradle/gradle,gradle/gradle,blindpirate/gradle,robinverduijn/gradle,blindpirate/gradle,robinverduijn/gradle,blindpirate/gradle,gradle/gradle,gradle/gradle-script-kotlin,gradle/gradle,gradle/gradle,blindpirate/gradle,gradle/gradle,blindpirate/gradle,blindpirate/gradle,blindpirate/gradle