Debug Property for "Create Test World"

Hello! In light of the fact that Mojang is making a lot of their debugging tools available to the public and removing code obfuscation, I would like to suggest the addition of a new debug property.

In Java Edition, there is code for a "Create Test World" option to appear on the main menu. However, it has no debug property, so this feature can't be enabled without modifying the game. Having a debug property for this would be very useful, as content creators could quickly create a world which is suitable for testing.