Stopping normalization of invalid html literals

[WhiteGobo]

Summary of changes

literal stops normalization process if html5lib cant parse literal
Tests now check, that invalid html literals wont be normalized

Fixes #2475

Checklist

• Checked that there aren't other open pull requests for
  the same change.
• Checked that all tests and type checking passes.
• If the change has a potential impact on users of this project:
  • Added or updated tests that fail without the change.
  • Updated relevant documentation to avoid inaccuracies.
  • Considered adding additional documentation.
• Considered granting push permissions to the PR branch,
  so maintainers can fix minor issues and keep your PR up to date.

[coveralls]

coverage: 90.926% (+0.02%) from 90.904% when pulling 29691f2 on WhiteGobo:stop_normalization_for_invalid_htmlliterals into e94c252 on RDFLib:main.

[aucampia]

Thanks for looking into this, it is indeed the right thing to do, however running the HTML5Lib parser in strict mode may be slightly better as that results in an exception with some more information about the error. We could technically recover the same information and add it in a custom exception, but errors is an array of errors and could indicate multiple errors.

[WhiteGobo]

Thank you for reviewing the code. Ive missed that option. Sounds good.

[aucampia]

pre-commit.ci autofix

[aucampia]

I'm going to merge this. I think there is still more wrong with the rdf:HTML stuff, but this should go in anyway.