Update android build configs (#534)

* Update compile sdk version
Update kotlin version

* Add missing HavenAccountList class to configure to be generated with haven.dart file

* Revert compile sdk and ndk changes

android/build.gradle

@@ -1,4 +1,5 @@
 buildscript {
+    ext.kotlin_version = '1.5.10'
     repositories {
         google()
         jcenter()
@@ -7,6 +8,7 @@ buildscript {
     dependencies {
         classpath 'com.android.tools.build:gradle:4.1.3'
         classpath 'com.google.gms:google-services:4.3.8'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }