Fix flaky specs due to label ordering

What does this MR do and why?

Label notes are ordered by name so we also order the assertion by name

Example failure:

     Failure/Error:
       expect(discussions.first.notes.map(&:note)).to match_array(
         ["added #{label.to_reference} #{label_2.to_reference} labels"]
       )
     
       expected collection contained:  ["added ~39 ~40 labels"]
       actual collection contained:    ["added ~40 ~39 labels"]
       the missing elements were:      ["added ~39 ~40 labels"]
       the extra elements were:        ["added ~40 ~39 labels"]

References

• #446092 (closed)
• #471170 (closed)
• #485907 (closed)
• #485908 (closed)

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.