PM-2109 "REST endpoint PUT /cases/{app_uid}/unpause..." SOLVED

> Code Issue:
  REST endpoint PUT /cases/{app_uid}/unpause can be called on a case which isn't paused
> Solution:
  Se agrega validacion cuando un caso NO esta pausado se mostrara un mensaje.

workflow/engine/src/ProcessMaker/BusinessModel/Cases.php

@@ -811,6 +811,12 @@ class Cases
         }
         Validator::isInteger($del_index, '$del_index');
 
+        $oDelay = new \AppDelay();
+
+        if (!$oDelay->isPaused($app_uid, $del_index)) {
+            throw (new \Exception(\G::LoadTranslation("ID_CASE_NOT_PAUSED", array($app_uid))));
+        }
+
         $case = new \Cases();
         $case->unpauseCase( $app_uid, $del_index, $usr_uid );
     }