Amended the logic for newPrefix in the MarkdownEditor to resolve
incorrect number ordering.
Fixes#33184
Attached screenshot of fixed input similar to issue
<img width="175" alt="Screenshot 2025-01-09 at 23 59 24"
src="https://github.com/user-attachments/assets/dfa23cf1-f3db-4b5e-99d2-a71bbcb289a8"
/>
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>