Update dependency happy-dom to ^15.8.4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
happy-dom	^15.8.3 -> ^15.8.4

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Release Notes

capricorn86/happy-dom (happy-dom)

### [`v15.8.4`](https://redirect.github.com/capricorn86/happy-dom/compare/v15.8.3...38ab960d0e1e3f230996cc163d78819290c91558) [Compare Source](https://redirect.github.com/capricorn86/happy-dom/compare/v15.8.3...v15.8.4)

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