• Forge version: forge - Minecraft Forge - 14.23.5.2847
• RTG version: rtg - Realistic Terrain Generation - 6.1.0.0-snapshot.1

Issue Description:

Please provide support for NetherEx.
https://www.curseforge.com/minecraft/mc-mods/netherex

I do not have other terrain mods installed nor do I have BOP installed.
[RTG]: || ID | Biome Class | Registry Name
[RTG]: || 73 | BiomeFungiForest | netherex:fungi_forest
[RTG]: || 74 | BiomeTorridWasteland | netherex:torrid_wasteland
[RTG]: || 75 | BiomeArcticAbyss | netherex:arctic_abyss

These are Nether biomes. RTG has never supported The Nether or The End, so supporting these biomes is pointless.