Fix Firebase Analytics setup and disable ad ID

apps/mobile/android/build.gradle

@@ -18,7 +18,7 @@ buildscript {
         classpath 'com.google.gms:google-services:4.4.1'
         classpath('com.android.tools.build:gradle')
         classpath('com.facebook.react:react-native-gradle-plugin')
-        classpath('org.jetbrains.kotlin:kotlin-gradle-plugin')
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion")
     }
 }