made itests catch MarathonHttpError

paasta_itests/steps/setup_marathon_job_steps.py

@@ -17,6 +17,7 @@
 import mock
 from behave import then
 from behave import when
+from marathon.exceptions import MarathonHttpError
 
 from paasta_tools import marathon_tools
 from paasta_tools import setup_marathon_job
@@ -104,7 +105,10 @@ def change_number_of_context_instances(context, number):
 @when(u'we run setup_marathon_job until the instance count is {number}')
 def run_setup_marathon_job(context, number):
     while context.marathon_client.get_app(fake_appid).instances != int(number):
-        create_complete_app(context)
+        try:
+            create_complete_app(context)
+        except MarathonHttpError:
+            continue
         time.sleep(1)