Allow public to view transaction details

Summary: Fixes T6427.

Test Plan: Log out of sandbox, navigate to public task, click 'See Details' in a transaction. Get Dialog.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T6427

Differential Revision: https://secure.phabricator.com/D10759

src/applications/transactions/controller/PhabricatorApplicationTransactionDetailController.php

@@ -5,6 +5,10 @@ final class PhabricatorApplicationTransactionDetailController
 
   private $phid;
 
+  public function shouldAllowPublic() {
+    return true;
+  }
+
   public function willProcessRequest(array $data) {
     $this->phid = $data['phid'];
   }