Hide "Land to hosted git" button for now
Summary: Ref T182. This feature rarely/never works and is on the balance enormously confusing to users (see https://github.com/facebook/phabricator/issues/566). If installs have somehow made it sort of work, they can comment this line out for now until we have time to make this work more reasonably.
Test Plan: Looked at a revision in Differential.
Reviewers: btrahan, chad
Reviewed By: chad
Maniphest Tasks: T182
Differential Revision: https://secure.phabricator.com/D8719