chore(deps): update dependency markdown-it-anchor to v9

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
markdown-it-anchor	^8.6.6 -> ^9.0.0

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Release Notes

valeriangalliat/markdown-it-anchor (markdown-it-anchor)

### [`v9.0.0`](https://togithub.com/valeriangalliat/markdown-it-anchor/blob/HEAD/CHANGELOG.md#900---2024-05-16) [Compare Source](https://togithub.com/valeriangalliat/markdown-it-anchor/compare/v8.6.7...v9.0.0) - Support markdown-it 14. This may be breaking hence the major. (\[[#​129](https://togithub.com/valeriangalliat/markdown-it-anchor/issues/129)], \[[#​128](https://togithub.com/valeriangalliat/markdown-it-anchor/issues/128)])

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Configuration

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