Update dependency markdown-it-footnote to v4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
markdown-it-footnote	^3.0.3 -> ^4.0.0

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Release Notes

markdown-it/markdown-it-footnote (markdown-it-footnote)

### [`v4.0.0`](https://togithub.com/markdown-it/markdown-it-footnote/blob/HEAD/CHANGELOG.md#400--2023-12-06) [Compare Source](https://togithub.com/markdown-it/markdown-it-footnote/compare/3.0.3...4.0.0) - Rewrite to ESM. - Remove `dist/` from repo (build on package publish).

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