build(deps): bump html5rdf from 1.2 to 1.2.1 (#3048)

Bumps [html5rdf](https://github.com/RDFLib/html5rdf) from 1.2 to 1.2.1.
- [Release notes](https://github.com/RDFLib/html5rdf/releases)
- [Changelog](https://github.com/RDFLib/html5rdf/blob/main/CHANGES.rst)
- [Commits](https://github.com/RDFLib/html5rdf/commits/v1.2.1)

---
updated-dependencies:
- dependency-name: html5rdf
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]