Parsing for attribution scopes

https://github.com/WICG/attribution-reporting-api/pull/1352

This CL modifies source and trigger registration parsing to include
attribution scopes, attribution scope limit, and max event states.

Bug: 344081621
Change-Id: I4cafb858cf2ec914d045f02a88a97ad0ec21b793
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5591266
Reviewed-by: Andrew Paseltiner <apaseltiner@chromium.org>
Reviewed-by: Nan Lin <linnan@chromium.org>
Reviewed-by: Dominic Farolino <dom@chromium.org>
Commit-Queue: Thomas Quintanilla <tquintanilla@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1329106}