Don't reject external LSX connections

[p0358]

This is a simple change to allow external LSX connections to be accepted. This works, though Maxima doesn't show the player state as in-game and I have no idea how this affects presence.

Why? Because the user might have external WINE prefix with a working game installation (it requires some mods to game), and LSX is just a TCP server. Personally for me launching games with Maxima doesn't seem to work at all currently, so this makes the difference between being able to use it at all or not... (this will work out of the box with Titanfall with my Black Market Edition mod in its next version)

The PR just makes the code not drop the connection if maxima.playing isn't populated, moving the PID grabbing code to conditionally happen only if it is.

INFO - [maxima::lsx::service] - New LSX connection: 127.0.0.1:47146
WARN - [maxima::lsx::connection] - External LSX connection (the game was not started through Maxima)
INFO - [maxima::lsx::request::challenge] - Game Connected - Name: Titanfall, Offer ID: 1011172, Multiplayer Id: 1011172
INFO - [maxima::lsx::request::auth] - Retrieving authorization code for 'TITANFALL'

[p0358]

Changed to draft, since it still has some issues:

INFO - [maxima::lsx::request::profile] - Setting Presence to Joinable: Private lobby

thread 'tokio-runtime-worker' (773397) panicked at maxima-lib/src/lsx/request/profile.rs:93:45:
called `Option::unwrap()` on a `None` value

Some changes will be needed, so that the offer id of a given connection can be retrieved.