Fix typos

Found via `typos --hidden --format brief`

Author: kianmeng

README.md

@@ -115,5 +115,5 @@ benchmarks/<file>`.
 
 ## Contributing
 
-- Pull requests that may be rebased are preferrable to merges or squashes.
+- Pull requests that may be rebased are preferable to merges or squashes.
 - Please **do not** increment the version number in pull requests.

test/integration/socket_test.exs

@@ -36,7 +36,7 @@ defmodule Absinthe.GraphqlWS.SocketTest do
     assert json == Jason.encode!(payload)
   end
 
-  describe "initalization" do
+  describe "initialization" do
     test "starts and stops" do
       assert {:ok, client} = Test.Client.start()
       Test.Client.close(client)