Android: Change the way doNotStrip is set

[Summersay415]

Update how doNotStrip is set by leveraging the project's extra properties.

See https://docs.gradle.org/current/javadoc/org/gradle/api/Project.html#properties for reference.

Fixes #92858

[m4gr3d]

@Summersay415 Can you link to the documentation for your change.

[Summersay415]

Documentation of Godot or Gradle?
If Godot, then here

[m4gr3d]

Documentation of Godot or Gradle? If Godot, then here

Documentation for gradle; from a quick google search, I cannot find any references to project.ext.doNotStrip.

[Summersay415]

This way property are added to the project to be detected by

ext.shouldNotStrip = { ->
    return isAndroidStudio() || project.hasProperty("doNotStrip")
}

Previous way of adding doNotStrip property didn't work and shouldNotStrip returned false even in dev build. This way of setting property works properly and symbols are saved in resulting template

[m4gr3d]

Sorry for the delay on this PR. I was able to confirm your fix is correct by checking the following documentation:

https://docs.gradle.org/current/javadoc/org/gradle/api/Project.html#properties

I've updated the PR's description to match.

[m4gr3d]

Thanks for the fix!

[akien-mga]

Thanks!