Bump @web/rollup-plugin-html from 2.0.1 to 2.1.2

Bumps [@web/rollup-plugin-html](https://github.com/modernweb-dev/web/tree/HEAD/packages/rollup-plugin-html) from 2.0.1 to 2.1.2.
- [Release notes](https://github.com/modernweb-dev/web/releases)
- [Changelog](https://github.com/modernweb-dev/web/blob/master/packages/rollup-plugin-html/CHANGELOG.md)
- [Commits](https://github.com/modernweb-dev/web/commits/@web/[email protected]/packages/rollup-plugin-html)

---
updated-dependencies:
- dependency-name: "@web/rollup-plugin-html"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>