build(deps-dev): bump postcss-html from 1.7.0 to 1.8.0

Bumps [postcss-html](https://github.com/ota-meshi/postcss-html) from 1.7.0 to 1.8.0.
- [Release notes](https://github.com/ota-meshi/postcss-html/releases)
- [Commits](ota-meshi/postcss-html@v1.7.0...v1.8.0)

---
updated-dependencies:
- dependency-name: postcss-html
  dependency-version: 1.8.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]