Migrate plugin to built-in Kotlin

[FlutterEngineers]

I am using firebase_analytics latest version in my Flutter app.

Starting with Android Gradle Plugin (AGP) 9.0,
support for applying the Kotlin Gradle Plugin (KGP) has been removed.
Because this plugin applies KGP,
it causes a compilation error that prevents my app from building.
Flutter issue #181383
includes an example of the error.

Flutter has temporarily added support to allow KGP
while apps and plugins migrate to AGP 9.0 or later,
but this support will be removed in a future version of Flutter.

Please migrate this plugin to use built-in Kotlin to
ensure your plugin users can successfully
build their apps in future versions of Flutter.

Here is the Flutter
migration guide for plugin authors.

[SelaseKay]

Hi @FlutterEngineers, thanks for the report. I'll look into this.