The expected assertion is specific to irregexp codegen.

Bug: chromium:1255368
Change-Id: I14d033285014727de2e63582ed798fc82570497d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3207892
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77254}