Remove incorrect DCHECK() in interaction_sequence.cc

This is a legacy DCHECK() that checks against functionality that is now
supported for InteractionSequences.

Change-Id: I8102231dc632c21d42270d3057ed31f60f5c07b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5420798


Commit-Queue: Vinny Persky <vinnypersky@google.com>
Reviewed-by: Dana Fried <dfried@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1282153}