Update error messages in sanity tests

Update error messages throughout sanity tests
to use the same (or similar) format of error message.

Change-Id: I4db0517a5b264151ddaa6ea2c2a04d37e139944e
Related-PROD: #PROD-32415
diff --git a/test_set/cvp-sanity/fixtures/base.py b/test_set/cvp-sanity/fixtures/base.py
index 822d908..560f906 100644
--- a/test_set/cvp-sanity/fixtures/base.py
+++ b/test_set/cvp-sanity/fixtures/base.py
@@ -29,7 +29,7 @@
 nodes = utils.calculate_groups()
 
 
-@pytest.fixture(scope='session', params=nodes.values(), ids=nodes.keys())
+@pytest.fixture(scope='session', params=nodes.items(), ids=nodes.keys())
 def nodes_in_group(request):
     return request.param