Update to the process of obtaining data-review for Firefox Desktop/Android and Gecko data collection

[Gijs Kruitbosch]

On May 7th, our process for requesting data-review for Firefox Desktop/Android & Gecko data collection is changing.

The process will largely move to Phabricator, much like code review, and Lando will enforce that appropriate data-review was obtained before changes land. For most people, this should simplify the mechanics of the process, as it will no longer involve copying templates into attachments on bugzilla. Instead, it will be very similar to annotating changes for test coverage.

Full details are on the wiki, with some technical minutiae due to appear on firefox-source-docs today.

Many thanks to the data stewards, conduit/phabricator teams and everyone else who was involved in getting this change over the line.

Gijs