Update dependency hexo to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
hexo (source)	devDependencies	major	3.9.0 -> 4.0.0

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Release Notes

hexojs/hexo

### [`v4.0.0`](https://togithub.com/hexojs/hexo/compare/3.9.0...9662366f9122192359f15861fe05574365e8465e) [Compare Source](https://togithub.com/hexojs/hexo/compare/3.9.0...9662366f9122192359f15861fe05574365e8465e)

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