Enable in-cct triggering for shopping and coupons.

The launched configs replace the legacy finch config and corresponding
tests.

- This also removes the "AutofillAssistantInTabTriggering" and
"AutofillAssistantUrlHeuristics" features - they are no longer needed.
- "AutofillAssistantInCctTriggering" is retained so we can turn this
off in the server if necessary.
- Removed the field trial testing config

Bug: b:239682654
Change-Id: I0c2a39008d3d95833f48eed52e88e0538a38dd1c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3885030
Reviewed-by: Luca Hunkeler <hluca@google.com>
Commit-Queue: Clemens Arbesser <arbesser@google.com>
Cr-Commit-Position: refs/heads/main@{#1051864}