tree fix (shiptest-ss13#2841)

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## About The Pull Request
fix tree variations not existing
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## Why It's Good For The Game
bugfix
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## Changelog

:cl:

fix: pine trees now correctly show all possible sprite variations

/:cl:

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code/game/objects/structures/flora.dm

@@ -68,7 +68,7 @@
 /obj/structure/flora/tree/pine/Initialize()
 	. = ..()
 
-	if(islist(icon_states && icon_states.len))
+	if(islist(icon_states) && icon_states.len)
 		icon_state = pick(icon_states)
 
 /obj/structure/flora/tree/pine/xmas