chore(deps): update reviewdog/action-markdownlint action to v0.20.0

[stackable-bot]

This PR contains the following updates:

Package	Type	Update	Change
reviewdog/action-markdownlint	action	minor	v0.18.0 -> v0.20.0

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Release Notes

reviewdog/action-markdownlint (reviewdog/action-markdownlint)

### [`v0.20.0`](https://togithub.com/reviewdog/action-markdownlint/releases/tag/v0.20.0) [Compare Source](https://togithub.com/reviewdog/action-markdownlint/compare/v0.19.0...v0.20.0) v0.20.0: PR [#​57](https://togithub.com/reviewdog/action-markdownlint/issues/57) - chore(deps): update markdownlint-cli to 0.41.0 ### [`v0.19.0`](https://togithub.com/reviewdog/action-markdownlint/releases/tag/v0.19.0) [Compare Source](https://togithub.com/reviewdog/action-markdownlint/compare/v0.18.0...v0.19.0) v0.19.0: PR [#​58](https://togithub.com/reviewdog/action-markdownlint/issues/58) - chore(deps): update reviewdog to 0.17.5

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