Adjust clientname parsing

[Tomato6966]

also shorten the code kept the checking for invalids

Changes

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Why

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Checkmarks

• [ ] The modified endpoints have been tested.
• [ ] Used the same indentation as the rest of the project.
• [ ] Still compatible with LavaLink clients.

Additional information

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[ThePedroo]

Superseded by https://github.com/PerformanC/NodeLink/commit/1281e520ffcf16b7913418be8bec6a252f6001a9.