Update error message for conflicting MRs
What does this MR do and why?
Iterating on !128414 (merged) by linking the referenced MR and updating the error message. We are not modifying the backend error string, and running this through a Banzai filter is overkill.
Screenshots or screen recordings
How to set up and validate locally
Related to #22015 (closed)
Edited by Kerri Miller