Looks like there's a problem with Android Studio 3.4 even already downloaded the android-21 build tools when using double quotes on buildToolsVersion "versionnumber" into buildToolsVersion = 'versionNumber'.
Change this
// dependencies.gradle
androidBuildToolsVersion = "24.0.1"
 
into
// dependencies.gradle
androidBuildToolsVersion = '24.0.1'
 
// data/build.gradle & presentation/build.gradle
buildToolsVersion = globalConfiguration["androidBuildToolsVersion"]