Fix possible inaccuracy for Swift Language

[varunudacity]

It seems that the Equatable protocol may be defined here:
https://github.com/apple/swift/blob/master/stdlib/public/core/Equatable.swift
I'm not a swift expert by any means, but it does appear that it's definable within the language.

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[KikeE36]

Parece que el protocolo Equatable se puede definir aquí:
https://github.com/apple/swift/blob/master/stdlib/public/core/Equatable.swift
No soy un experto rápido de ninguna manera, pero lo es parece que es definible dentro del idioma.