Remove load balancing module from index.yml

Removed module for load balancing web traffic.

Author: rmcmurray

learn-pr/paths/architect-network-infrastructure/index.yml

@@ -30,7 +30,6 @@ subjects:
 - architecture
 modules:
 - learn.secure-and-isolate-with-nsg-and-service-endpoints
-- learn.load-balance-web-traffic-with-application-gateway
 - learn.control-network-traffic-flow-with-routes
 trophy:
   uid: learn.architect-network-infrastructure.trophy