Add Jekyll logo to project templates

What does this MR do?

Implements #28686 (closed) by adding the Jekyll logo to project templates.

Screenshots

Before	After

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content