Multiple `&` references inside `:is()`, `:where()`, `:has()` not fully resolved

[quantizor]

Description

When multiple & (parent selector) references appear inside :is(), :where(), or :has() pseudo-class arguments, stylis only resolves the first & but leaves subsequent ones as literal & characters.

Reproduction

import { compile, serialize, stringify } from 'stylis';

const result = compile('.parent .child { :is(&:hover, .other:hover &) .target { color: red; } }');
console.log(serialize(result, stringify));

Expected output

:is(.parent .child:hover, .other:hover .parent .child) .target{color:red;}

Actual output

:is(.parent .child:hover, .other:hover &) .target{color:red;}

The second & in the :is() arguments is not replaced with the parent selector.

Environment

stylis 4.3.6