[BEHAVIOUR DIFFERENCE] Client don't get any messages when you enter an invalid nickname

Describe the bug
On open.mp you don't get any messages telling you that the chosen nickname isn't valid. This happens either if you use unacceptable characters or if you enter the same nickname of an already online player. You only get the "Server closed connection" message.

To Reproduce
Steps to reproduce the behavior:

1. Choose a nickname with an unacceptable character or enter the same nickname of another already online player
2. Connect to the server

Expected behavior
This is what it should happen.

{FFFFFF}SA-MP {B9C9BF}0.3.7-R5 {FFFFFF}Started

Connecting to 46.105.43.212:8888...

Connected. Joining the game...

CONNECTION REJECTED: Unacceptable NickName

Please choose another nick between and 3-20 characters

Please use only a-z, A-Z, 0-9

Use /quit to exit or press ESC and select Quit Game

Screenshots and/or logs
SA:MP behaviour:

open.mp behaviour:

Commit hash in master
(https://github.com/openmultiplayer/open.mp/commit/441a63a74712003d8a3c05745cc30c93f07922ff)