(Java Parity) Remove obsolete sub-biomes

In the Java snapshots, the sub-biomes that are no longer needed for biome transitions and height differences have been removed. While in the Bedrock betas they no longer spawn, they are still left in the code. They should be removed for full biome parity. In addition, the biomes in Bedrock that have been renamed in Java, have not been renamed in Bedrock yet either. I'm not sure if it's an oversight that these changes haven't been made on Bedrock yet, or if it is planned later, or not at all. But it needs to be done.