Update _default.cfg

[rackgaming]

ATS needs to be launched via the server_launch.sh file and not amtrucks_server then it works, has been tested by me! Also, people need to realize they need to export_server_packages for ATS by starting their ATS game first and loading their game save then use WinSCP to find their .local directory as some server hosters may have this directory hidden(or at least my linux server had the .local directory hidden), anyway this should fix the current problem of the game server not starting, the rest is in the post stated hereto fix the game server from missing things: #4580

Description

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Fixes #[issue]

Type of change

• Bug fix (a change which fixes an issue).
• New feature (a change which adds functionality).
• New Server (new server added).
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Documentation

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• User docs: https://github.com/GameServerManagers/LinuxGSM-Docs
• Dev docs: https://github.com/GameServerManagers/LinuxGSM-Dev-Docs

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