Finalize spawn targets are not being updated

[Shadows-of-Fire]

Since the change to NG, the findFinalizeSpawnTargets task was removed

NeoForge/build.gradle

Lines 873 to 883 in a3317fc

	task findFinalizeSpawnTargets(type: BytecodePredicateFinder, dependsOn: ['createJoinedSRG']) {
	jar = createJoinedSRG.output
	output = rootProject.file('src/main/resources/coremods/finalize_spawn_targets.json')
	predicate = {
	parent, node, insn ->
	'net/minecraft/world/level/BaseSpawner' != parent.name // Ignore this class as we special case it.
	&& insn.getOpcode() == Opcodes.INVOKEVIRTUAL
	&& insn.name.equals('m_6518_')
	&& insn.desc.equals('(Lnet/minecraft/world/level/ServerLevelAccessor;Lnet/minecraft/world/DifficultyInstance;Lnet/minecraft/world/entity/MobSpawnType;Lnet/minecraft/world/entity/SpawnGroupData;Lnet/minecraft/nbt/CompoundTag;)Lnet/minecraft/world/entity/SpawnGroupData;')
	}
	}

This task is needed to ensure that our FinalizeSpawnEvent is fired appropriately for all vanilla cases. To re-implement this, we need something akin to BytecodePredicateFinder from FG that allows the vanilla classes to be scanned for target instructions.