[Android] Unbatch TabsTest to isolate failures

The test already had hidden flakes and local failures, and extracting
out ToolbarSwipeTest added even more hidden flakes. The disabled tests
in this suite are likely disabled due to side effects too.

This CL unbatches the test because it's not workable in its current
batched state. The test cases need to be fixed to work locally and
vetted on CI separately before trying to batch them again.

Bug: 40854790,324292358, 40857394, 328470939
Change-Id: I3d10a83ed24ddd645b967754dbbe7fb8c1bac86a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5356636


Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1271719}