Fixes a typo causing caps to display contained items when not worn (#…

…4689)

# About the pull request

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A small oopsie made it so caps still displayed contained items when they
were held and not worn. This fixes that.

Thanks to joooks for reporting

# Explain why it's good for the game
Consistency


# Testing Photographs and Procedure
spawn in as SO, with mgoggles, switch between hand and equipped


# Changelog
:cl:
fix: Fixed caps displaying contained items on character even without
being worn.
/:cl:

code/modules/clothing/head/head.dm

@@ -308,8 +308,8 @@
 
 /obj/item/clothing/head/cmcap/get_mob_overlay(mob/user_mob, slot)
 	var/image/return_image = ..()
-	if(!slot == WEAR_HEAD)
-		return
+	if(slot != WEAR_HEAD)
+		return return_image
 
 	if(length(pockets.contents) && (flags_marine_hat & HAT_GARB_OVERLAY))
 		for(var/obj/garb_object in pockets.contents)