docs: add Nekoya3 as a contributor

[allcontributors[bot]]

Adds @Nekoya3 as a contributor for code.

This was requested by Nekoya3 in this comment

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[NEKOYASAN]

@all-contributors please add Nekoya3 for code, ideas

[allcontributors[bot]]

@Nekoya3

I've put up a pull request to add @Nekoya3! :tada: