Fix incorrect maniphest.update conduit UI

Summary: Fixes T6254 and renames status as string. Though maybe this should go through `formatStringConstants`?

Test Plan: Reload Conduit page, see new text.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T6254

Differential Revision: https://secure.phabricator.com/D10637

src/applications/maniphest/conduit/ManiphestConduitAPIMethod.php

@@ -42,7 +42,7 @@ abstract class ManiphestConduitAPIMethod extends ConduitAPIMethod {
 
     if (!$is_new) {
       $fields += array(
-        'status'    => 'optional int',
+        'status'    => 'optional string',
         'comments'  => 'optional string',
       );
     }