Bump html-proofer from 3.17.2 to 3.17.3
Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.17.2 to 3.17.3. - [Release notes](https://github.com/gjtorikian/html-proofer/releases) - [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.17.2...v3.17.3)