[#] Fixed a crash caused by the voicechat module on full server shutdown.
We create a ISteamUser but when we try to clean it up it was already invalid which then crashed steam.
Why was it invalid?
Because the engine calls SteamGameServer_Shutdown which already invalidates all ISteamUser's so our reference becomes junk.
Now we handle this case properly and it won't crash anymore.
This issue has existed for many months and was utterly difficult to debug as no valid crash dump were created the entire time
See the Issue: #41
NOTE: The linked GH commit is a lie.
The real branch for this release is: https://github.com/RaphaelIT7/gmod-holylib/tree/Release0.72