Allow JobStorage to reset the EntityManager

After a Job triggers a Doctrine exception, and handles it, the EntityManager still remains closed and JobStorage can't persist changes. This fix resets the Manager after such an occurrence.

Author: damijank

pkg/job-queue/Doctrine/JobStorage.php

@@ -212,6 +212,9 @@ private function getEntityManager()
         if (!$this->em) {
             $this->em = $this->doctrine->getManagerForClass($this->entityClass);
         }
+        if (!$this->em->isOpen()) {
+            $this->em = $this->doctrine->resetManager();
+        }
 
         return $this->em;
     }