replace submodule skybox

.gitmodules

@@ -299,9 +299,9 @@
 [submodule "mods/moreglass"]
 	path = mods/moreglass
 	url = https://github.com/dafoxia/moreglass
-[submodule "mods/skybox"]
-	path = mods/skybox
-	url = https://github.com/minetest-mods/skybox
 [submodule "mods/spawners"]
 	path = mods/spawners
 	url = https://git.tchncs.de/Illuna-Minetest/spawners
+[submodule "mods/skybox"]
+	path = mods/skybox
+	url = https://git.tchncs.de/Illuna-Minetest/skybox