Newlines in custom server hook error messages render improperly in merge UI

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Summary

Newlines in custom system hook error messages do not render correctly in the merge request UI on attempted merge.

Steps to reproduce

Create a new repository with an empty README.md. Create a new branch within that repository with some arbitrary content and submit a merge request.

Then create a custom hook within the given repository with a multiple messages, as follows:

#!/bin/sh

echo "GL-HOOK-ERR: User is ${GL_ID}"
echo "GL-HOOK-ERR: Do better."
exit 1

Finally attempt to merge that MR.

What is the current bug behavior?

Newlines are replaced and rendered as literal <br> but not rendered as html (so are displayed literally).

What is the expected correct behavior?

Messages should be displayed on separate lines, as appropriate.

Relevant logs and/or screenshots

The problem:

How it should (and does display in the edit/commit UI):

Possible fixes

Relevant bit of code, but not necessarily where to fix this:
https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/utils.rb#L94