fix: ignore relative selector lists when resolving multiple selectors

[1000hz]

Description

fela-multiple-selectors-plugin currently naively splits selectors on ,, but this doesn't account for relative selector lists that may be within a pseudo-class. This results in invalid selectors being resolved.

This PR fixes that issue by making use of lookahead and lookbehind assertions when splitting to avoid matching within pseudo-class selector lists.

Example

:not(:hover, :focus) {}

currently resolves to :not(:hover and :focus), both of which are invalid.

With this PR, the selector remains whole as :not(:hover, :focus).

Packages

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• fela-plugin-multiple-selectors

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