[TF] Skip check external connectivity (PRODX-5188)

Related-PROD: PRODX-5188
Change-Id: I89bf1ac6d5aed97023b6601d321fbc35d62000e2
diff --git a/tempest/scenario/test_network_basic_ops.py b/tempest/scenario/test_network_basic_ops.py
index d8584ec..0e89ae3 100644
--- a/tempest/scenario/test_network_basic_ops.py
+++ b/tempest/scenario/test_network_basic_ops.py
@@ -421,7 +421,9 @@
         self._setup_network_and_servers()
         self._check_public_network_connectivity(should_connect=True)
         self._check_network_internal_connectivity(network=self.network)
-        self._check_network_external_connectivity()
+        # (PRODX-5188) Skip check connectivity with gateway:
+        if not CONF.service_available.contrail:
+            self._check_network_external_connectivity()
         self._disassociate_floating_ips()
         self._check_public_network_connectivity(should_connect=False,
                                                 msg="after disassociate "