Close the session properly - part 2

src/render_queue.py

@@ -88,10 +88,11 @@ class RenderQueue:
 
     @classmethod
     def prepare_for_shutdown(cls):
+        logger.debug("Closing session")
         running_jobs = cls.jobs_with_status(RenderStatus.RUNNING)  # cancel all running jobs
-        for job in running_jobs:
-            cls.cancel_job(job)
+        [cls.cancel_job(job) for job in running_jobs]
         cls.save_state()
+        cls.session.close()
 
     @classmethod
     def is_available_for_job(cls, renderer, priority=2):