fix: remove buildToolsVersion (#615)

remove buildToolsVersion

Author: dulmandakh

android/build.gradle

@@ -74,7 +74,6 @@ if (useNextStorage) {
 
 android {
     compileSdkVersion safeExtGet('compileSdkVersion', 28)
-    buildToolsVersion safeExtGet('buildToolsVersion', '28.0.3')
     defaultConfig {
         minSdkVersion safeExtGet('minSdkVersion', 19)
         targetSdkVersion safeExtGet('targetSdkVersion', 28)