Remove ERR_FAIL_COND that never happens in _draw_sky
Remove ERR_FAIL_COND that never happens in _draw_sky

In the conditional `sky` is always true.

vkbsb/godot,guilhermefelipecgs/godot,godotengine/godot,pkowal1982/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,godotengine/godot,guilhermefelipecgs/godot,guilhermefelipecgs/godot,josempans/godot,godotengine/godot,BastiaanOlij/godot,vkbsb/godot,josempans/godot,godotengine/godot,pkowal1982/godot,BastiaanOlij/godot,godotengine/godot,godotengine/godot,josempans/godot,sanikoyes/godot,vkbsb/godot,BastiaanOlij/godot,pkowal1982/godot,josempans/godot,pkowal1982/godot,BastiaanOlij/godot,vkbsb/godot,BastiaanOlij/godot,sanikoyes/godot,pkowal1982/godot,pkowal1982/godot,godotengine/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,BastiaanOlij/godot,godotengine/godot,pkowal1982/godot,sanikoyes/godot,sanikoyes/godot,josempans/godot,guilhermefelipecgs/godot,josempans/godot,vkbsb/godot,guilhermefelipecgs/godot,sanikoyes/godot,vkbsb/godot,guilhermefelipecgs/godot,sanikoyes/godot,vkbsb/godot,josempans/godot,sanikoyes/godot,sanikoyes/godot,vkbsb/godot,josempans/godot,pkowal1982/godot