[regexp] Don't propagate lookaround eats_at_least to surroundings

Lookarounds rewind the position after matching, and thus don't play
well with eats_at_least (EAL). This CL disables EAL propagation from
lookarounds.

In the future we could be a bit smarter by skipping over lookarounds
instead of resetting to 0.

Bug: v8:11290
Change-Id: I935400a7f9cda96d9c5a80e412ba7d04de70a84f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2808944


Reviewed-by: Seth Brenith <seth.brenith@microsoft.com>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73849}