Fix Phortune Subscription high-security checkpoint URI

Summary: This URI is currently a little whack.

Test Plan:
  - With MFA, clicked "Edit Subscription" on a subscription.
  - Clicked "Cancel".
    - Before: Sent to `/phortune/phortune/edit/...`, a 404.
    - After: Properly returned to subscription detail page.

Reviewers: chad

Reviewed By: chad

Differential Revision: https://secure.phabricator.com/D15514

src/applications/phortune/controller/PhortuneSubscriptionEditController.php

@@ -21,7 +21,7 @@ final class PhortuneSubscriptionEditController extends PhortuneController {
     id(new PhabricatorAuthSessionEngine())->requireHighSecuritySession(
       $viewer,
       $request,
-      $this->getApplicationURI($subscription->getEditURI()));
+      $subscription->getURI());
     $merchant = $subscription->getMerchant();
     $account = $subscription->getAccount();