chore(deps): update dependency markdownlint-cli to v0.28.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
markdownlint-cli	0.27.1 -> 0.28.1

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Release Notes

igorshubovych/markdownlint-cli

### [`v0.28.1`](https://togithub.com/igorshubovych/markdownlint-cli/releases/v0.28.1) [Compare Source](https://togithub.com/igorshubovych/markdownlint-cli/compare/v0.28.0...v0.28.1) - Fix outdated reference to `rc` (thanks [@​shhdgit](https://togithub.com/shhdgit)!) ### [`v0.28.0`](https://togithub.com/igorshubovych/markdownlint-cli/releases/v0.28.0) [Compare Source](https://togithub.com/igorshubovych/markdownlint-cli/compare/v0.27.1...v0.28.0) - Add `--json` option to output results in JSON format - Switch `rc` dependency to `run-con` to address `CVE-2020-7788` - Update all dependencies via `Dependabot`

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