feat: improve validation error on unlicensed components

[nijel]

Include links to problematic components to make it easier to address.

Issue #13896

[sentry-io]

Suspect Issues

This pull request was deployed and Sentry observed the following issues:

• ‼️ InvalidTemplateLibrary: Invalid template library specified. ImportError raised when trying to load 'weblate.trans.templatetags.translations': cannot import name 'format_html_join_comma' from 'weblate.utils.html' (/home/nijel/weblate/weblate/weblate/utils/html.py) django.template.backends.django in get_package_... View Issue

_{Did you find this useful? React with a 👍 or 👎}