[CVV Storage] Adding syncing of Local changes to the Chrome sync servers

Whenever any local storage change occurs for the Server cvc, we will
trigger a sync of the same to the Chrome sync servers.

DD- go/pay-autofill-cvv-storage-chrome

AutofillWebDataServiceObserverOnDBSequence will be implemented by the
sync bridge.

Low-Coverage-Reason: This component will be tested when
Bug: 1458044
Change-Id: Iec72aeb18c4f02fbe182f10a170681645dad635e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4766968
Reviewed-by: Alexander Tekle <alexandertekle@google.com>
Reviewed-by: Marc Treib <treib@chromium.org>
Reviewed-by: Siyu An <siyua@chromium.org>
Commit-Queue: Vipul Koul <koulvipul@google.com>
Reviewed-by: Dominic Battre <battre@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1188575}