R1:6d8167503266

Remove "url" from Elasticsearch index

Summary:
Ref T12450. This was added a very very long time ago (D2298).

I don't want to put this in the upstream index anymore because I don't want to encourage third parties to develop software which reads the index directly. Reading the index directly is a big skeleton key which bypasses policy checks.

This was added before much of the policy model existed, when that wasn't as much of a concern. On a tecnhnical note, this also doesn't update when `phabricator.base…