Fix ValueError in services details page

Deploy a environment, then go the environment details page,
click the services name link, will gives the error:
ValueError: Need 2 values to unpack in for loop; got 1.

This patch fix this error.

Change-Id: Id8c601b20eb9159d580f2e8fbfb1ee3967a00784
Closes-bug: #1703197

muranodashboard/environments/views.py

@@ -134,7 +134,7 @@ class DetailServiceView(tabs.TabbedTableView):
             (context["environment_name"],
              reverse("horizon:app-catalog:environments:services",
                      args=[self.environment_id])),
-            (_('Applications'),), ]
+            (_('Applications'), None)]
         context["custom_breadcrumb"] = breadcrumb
         return context
 

muranodashboard/tests/unit/environments/test_views.py

@@ -204,7 +204,7 @@ class TestDetailServiceView(testtools.TestCase):
             'environment_name': 'foo_env_name',
             'custom_breadcrumb': [
                 ('foo_env_name', 'foo_reverse_url'),
-                (_('Applications'),),
+                (_('Applications'), None)
             ]
         }