Re-enable SearchEngineChoiceUIPixelTest

Bug: 335549659
Change-Id: I231fa0300a3bb56e06f68509f2d9a248640e83d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5463026


Commit-Queue: Jack Yammine <jyammine@google.com>
Auto-Submit: Peng Huang <penghuang@chromium.org>
Reviewed-by: Jack Yammine <jyammine@google.com>
Cr-Commit-Position: refs/heads/main@{#1289311}