_V5TradeWebSocketManager: Send error messages on callback_function

[nietsuu]

I am using the WebSocketTrading and noticed that it doesn't send the error messages on the callback. It just logs the error on _V5TradeWebSocketManager._process_error_message.

I'm thinking it would be better to just send the error messages on the callback instead of logging it.

[nietsuu]

I think the current way of handling errors won't do (just logging it). Because sometimes you need to catch the errors and currently there is no way of doing that.

If this PR is not plausible. Maybe we can add another callback like error_callback solely for catching the error messages.

[kolya5544]

Code changes look good to me, however backwards compatability implications should be considered for people updating from older pybit versions

[nietsuu]

I think it's safe to assume that everyone that uses this don't have a code that results in error. So if they update, it really won't break anything.

And if they do have an error, they will still have to fix it anyways.
So it shouldn't be a concern in terms of compatibility in my opinion.