Solve race condition in tests

Author: josevalim

lib/elixir/test/elixir/process_test.exs

@@ -89,7 +89,6 @@ defmodule ProcessTest do
  assert Process.cancel_timer(timer, async: true)
  assert_receive {:cancel_timer, ^timer, result}
  assert is_integer(result)
- assert Process.cancel_timer(timer, info: false) == :ok
  end
 
  test "exit(pid, :normal) does not cause the target process to exit" do