Repeating mech repair (#3775)

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:cl:
fix: mech repair now loop
/:cl:

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Signed-off-by: Theos <[email protected]>

code/game/mecha/mecha_defense.dm

@@ -300,7 +300,7 @@
 		clearInternalDamage(MECHA_INT_TANK_BREACH)
 		to_chat(user, span_notice("You repair the damaged gas tank."))
 		return
-	if(obj_integrity < max_integrity)
+	while(obj_integrity < max_integrity)
 		if(!do_after(user, 20, target= src))
 			return
 		if(!W.use_tool(src, user, 0, volume=50, amount=1))