Resolve "Labeling system notes downcase labels"

What does this MR do?

This MR fixes issues of label gets lowercase in system note as describe in #24737 (closed)

Are there points in the code the reviewer needs to double check?

NR

Why was this MR needed?

This MR fixes the regression of becoming labels and its description and title lowercase in system note

Screenshots (if relevant)

Before:

After:

Does this MR meet the acceptance criteria?

• Changelog entry added
• 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

What are the relevant issue numbers?

Closes #24737 (closed) Closes #24751 (closed)