Resolve "Markdown blockquote is not displaying properly"

What does this MR do?

Fixes support for blockquotes compiled by markdown.

Why was this MR needed?

#47115 (closed)

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• [ ] Changelog entry added, if necessary
• [ ] Documentation created/updated
• [ ] API support added
• [ ] Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • [ ] Has been reviewed by a Backend maintainer
  • [ ] Has been reviewed by a Database specialist
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #47115 (closed)