battle process exit after some time

This is a temporary measure until we hook these process with autohost
messages.

lib/teiserver/tachyon_battle/battle.ex

@@ -36,6 +36,11 @@ defmodule Teiserver.TachyonBattle.Battle do
       autohost_timeout: Map.get(args, :autohost_timeout, 10)
     }
 
+    # because the battle system is not yet hooked up with anything whenever
+    # a battle is started it'll stay around forever. So to be 100% sure that
+    # it's not going to cause any issue, shut down the battle after some time
+    :timer.send_after(5 * 60_000, :die)
+
     case Teiserver.Autohost.lookup_autohost(autohost_id) do
       {pid, _} ->
         Logger.info("init battle for autohost #{autohost_id}")
@@ -59,6 +64,11 @@ defmodule Teiserver.TachyonBattle.Battle do
     {:stop, :normal, state}
   end
 
+  def handle_info(:die, state) do
+    Logger.info("Battle shutting down to save resources")
+    {:stop, :normal, state}
+  end
+
   defp via_tuple(battle_id) do
     Registry.via_tuple(battle_id)
   end