chore(deps): update peaceiris/actions-mdbook action to v2

[btkostner-infrastructure[bot]]

This PR contains the following updates:

Package	Type	Update	Change
peaceiris/actions-mdbook	action	major	v1.2.0 -> v2.0.0

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Release Notes

peaceiris/actions-mdbook (peaceiris/actions-mdbook)

### [`v2.0.0`](https://togithub.com/peaceiris/actions-mdbook/releases/tag/v2.0.0): actions-mdbook v2.0.0 [Compare Source](https://togithub.com/peaceiris/actions-mdbook/compare/v1.2.0...v2.0.0) See [CHANGELOG.md](https://togithub.com/peaceiris/actions-mdbook/blob/v2.0.0/CHANGELOG.md) for more details.

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Configuration

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