Remove duplicative koan

This truth is self-evident from the other koans.

lib/koans/18_genservers.ex

@@ -98,11 +98,6 @@ defmodule GenServers do
     assert is_pid(pid) == ___
   end
 
-  koan "When starting a GenServer you can set it's initial state" do
-    {:ok, pid} = GenServer.start_link(Laptop, "3kr3t!")
-    assert GenServer.call(pid, :get_password) == ___
-  end
-
   koan "The handle_call callback is synchronous so it will block until a reply is received" do
     {:ok, pid} = GenServer.start_link(Laptop, "3kr3t!")
     assert GenServer.call(pid, :get_password) == ___

test/koans/genservers_koans_test.exs

@@ -6,7 +6,6 @@ defmodule GenServersTests do
     answers = [
       true,
       "3kr3t!",
-      "3kr3t!",
       {:multiple, ["Apple Inc.", "MacBook Pro"]},
       {:multiple, [["2.9 GHz Intel Core i5"], 8192, :intel_iris_graphics]},
       "73x7!n9",