Add possibility to override (parts of) the template of the check SEO page

[jgadelange]

Is your feature request related to a problem? Please describe. Currently on the check seo page there is a sidebar with information on the django-check-seo package. However, this isn't very useful for content editors.

Describe the solution you'd like I would like to be able to override parts of the template without having to copy the whole template as a whole. I think we could achieve this by adding {% block%} tags.

Describe alternatives you've considered N/A

Additional context The sidebar I'm talking about: