Drowned spawning in the dripstone caves does not work, due to an error in the code

The reason why drowned aren’t spawning in the dripstone caves is due to an error in the spawn code, for dripstone caves, the drowned are set to “spawns_on_surface” instead of “spawns_underground”, which means they will only spawn in dripstone cave aquifers exposed to the surface. Changing the “on_surface” to “underground” fixes this and allows them to spawn, but preferably, simply add “spawns_underground” below spawns on surface allows them to spawn in all dripstone cave aquifers regardless of if there is air exposure or not