MineClone2 compatibility

[rm369]

For compatibility with https://git.minetest.land/MineClone2/MineClone2/ :

--- pi/worlds/1/.minetest/mods/spawn_command/depends.txt 2021-01-14 17:40:09.000000000 +0100
+++ pi/worlds/2/.minetest/mods/spawn_command/depends.txt 2021-03-27 15:30:59.760044515 +0100
@@ -1,2 +1,3 @@
-default
+default?
+mcl_core?
cursed_world?