Create commit conventions filter

What does this MR do?

Adds user's avatar and link based on mail or username in the description of a commit using commit message conventions.

Why was this MR needed?

In order to visually enhance the commit description and easily find relevant user info inside the commit description.

Screenshots (if relevant)

Before

After

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• [] Internationalization required/considered

What are the relevant issue numbers?

Closes #31640 (closed)