Entity Damage: Correct sign entity name

Reported by VanessaE

advtrains/trainlogic.lua

@@ -703,7 +703,7 @@ function advtrains.train_step_c(id, train, dtime)
 				local objs = minetest.get_objects_inside_radius(rcollpos, 2)
 				for _,obj in ipairs(objs) do
 					if not obj:is_player() and obj:get_armor_groups().fleshy and obj:get_armor_groups().fleshy > 0 
-							and obj:get_luaentity() and obj:get_luaentity().name~="signs:text" then
+							and obj:get_luaentity() and obj:get_luaentity().name~="signs_lib:text" then
 						obj:punch(obj, 1, { full_punch_interval = 1.0, damage_groups = {fleshy = 1000}, }, nil)
 					end
 				end