Update dependency xo to v0.28.1

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
xo	devDependencies	patch	0.28.0 -> 0.28.1

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Release Notes

xojs/xo

### [`v0.28.1`](https://togithub.com/xojs/xo/compare/v0.28.0...v0.28.1) [Compare Source](https://togithub.com/xojs/xo/compare/v0.28.0...v0.28.1)

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