Render PDFs in GitLab

What does this MR do?

• Add ability to render PDFs found in Project repos within GitLab

Why was this MR needed?

Screenshots (if relevant)

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together