Official Godot Android billing library now deprecated

[PickleJesus123]

As of November 1st 2023 (tomorrow), Google Play billing v4 will be entirely deprecated. The problem is, the master branch of the official Godot Google Play Billing plugin specifically targets this deprecated v4. However, there is another branch (billing-v5) which is up to date and working great, and it should become the new 'master' branch. It doesn't seem like the maintainers have checked in on the Android billing library in a while...

I would be happy to submit a PR that updates the documentation for the plugin, if someone would make billing-v5 the master branch

[Calinou]

Closing in favor of godot-sdk-integrations/godot-google-play-billing#59, as this is a bug and not a feature proposal.