Add check for floating_network_name

If router_external is present in pillar or not

Change-Id: Idbc3b58d343cb890fdd97dcedbddfae686096697
Related-Prod: PROD-22072 (PROD:22072)
diff --git a/_modules/runtest/tempest_sections/heat_plugin.py b/_modules/runtest/tempest_sections/heat_plugin.py
index 46731d9..87f11c4 100644
--- a/_modules/runtest/tempest_sections/heat_plugin.py
+++ b/_modules/runtest/tempest_sections/heat_plugin.py
@@ -145,7 +145,7 @@
         if not networks:
             return
         for network_name, network in networks.items():
-            if network['router_external'] is True:
+            if network.get('router_external') is True:
                 return network_name
 
     @property
diff --git a/_modules/runtest/tempest_sections/network.py b/_modules/runtest/tempest_sections/network.py
index af1be32..b66d510 100644
--- a/_modules/runtest/tempest_sections/network.py
+++ b/_modules/runtest/tempest_sections/network.py
@@ -59,7 +59,7 @@
         if not networks:
             return
         for network_name, network in networks.items():
-            if network['router_external'] is True:
+            if network.get('router_external') is True:
                 return network_name
 
     @property