Replace direct uses of GameTicker dictionary with TryGetValue

[ficcialfaint]

About the PR

Why / Balance

• The following is copied from my messages in #contributors chat (https://discord.com/channels/310555209753690112/770682801607278632/1302357518504165377)

Apparently if a player's SessionStatus stays on Connected for whatever reason, station events and antag selection might break in some way. The issue is some functions try to get a value from PlayerGameStatuses dictionary without checking if the player exists or not. For example:

var players = _playerManager.Sessions
    .Where(x => GameTicker.PlayerGameStatuses[x.UserId] == PlayerGameStatus.JoinedGame)
    .ToList();

The thing is that _playerManager.Sessions contains any sessions (including the Connected ones) while PlayerGameStatuses does not, meaning that if there's a player stuck (intentionally or not) on Connected, that specific line would throw an error The key 'blahblah' was not present in the dictionary.

And this possibly can lead to station events spam.
Not sure exactly this is the issue of events spam, but I've been reported about this and when looking at the logs the only errors I could find is The key 'blahblahblah' was not present in the dictionary and the stacktrace leading to UserHasJoinedGame(NetUserId userId) which is basically this:

public bool UserHasJoinedGame(NetUserId userId)
    => PlayerGameStatuses[userId] == PlayerGameStatus.JoinedGame;

Technical details

Replaced all^* PlayerGameStatuses[user] == Something with PlayerGameStatuses.TryGetValue(user, out var status) && status == Something

^* — except its usages in integration tests because I believe there is no chance to get the error in the tests (lmk if I'm wrong thinking that way)

Media

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Requirements

• I have read and am following the Pull Request and Changelog Guidelines.
• I have added media to this PR or it does not require an ingame showcase.

Breaking changes

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Changelog
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