handle exceptions in get_driver_version()

vmdriver.py

@@ -621,12 +621,16 @@ def get_ram_size():
 @celery.task
 def get_driver_version():
     from git import Repo
+    try:
         repo = Repo(path=os.getcwd())
         lc = repo.log()[0]
         return {'branch': repo.active_branch,
                 'commit': lc.id_abbrev,
                 'commit_text': lc.summary,
                 'is_dirty': repo.is_dirty}
+    except:
+        logging.exception("Unhandled exception: ")
+        return None
 
 
 @celery.task