Return an :ok on the cookie security setup (erlef#45)

Author: stilwellc

Diff for: modules/2-owasp.livemd

@@ -11,7 +11,6 @@ Mix.install([
 
 md5_hash = :crypto.hash(:md5, "users_password")
 bcrypt_salted_hash = Bcrypt.hash_pwd_salt("users_password")
-
 :ok
 ```
 

Diff for: modules/6-cookies.livemd

@@ -6,6 +6,7 @@ Mix.install([:phoenix, :plug])
 alias Phoenix.ConnTest
 alias Plug
 conn = ConnTest.build_conn()
+:ok
 ```
 
 ## Introduction