fix timeout

Author: greg-rychlewski

lib/ecto/adapters/myxql.ex

@@ -562,7 +562,7 @@ defmodule Ecto.Adapters.MyXQL do
     port_opts = port_opts(cmd_opts, args: args)
     port = Port.open({:spawn_executable, cmd}, port_opts)
     Port.command(port, contents)
-    Port.close(port)
+    Port.command(port, "\n")
 
     {initial, fun} = Collectable.into("")