refactor: deprecate imperative apply of Flutter's Gradle plugins

[alestiago]

Note: This issue was originally raised in Very Good CLI by @yuruyuri16 (VeryGoodOpenSource/very_good_cli#968)

Description

Since Flutter 3.16, Flutter's Gradle plugins are now applied using the Plugin DSL syntax instead of the legacy script syntax. See the official migration document.

Steps To Reproduce

1. Create a very good flutter app
2. Run in android and some deprecation messages will pop up.

Expected Behavior
Run with no warnings.

Screenshots

Requirements

• Update all our Android templates that are relying on the imperative apply of Flutter's Gradle Plugins

[alestiago]

@yuruyuri16 would you like to take care of wear_app and flame_game too? If so, I can assign this issue to you entirely.