Update aspnetapp.yaml port number (#1573)

The image uses 8080 port internally, so changed the service and pod like that

Author: uday1kiran

docs/examples/aspnetapp.yaml

@@ -9,7 +9,7 @@ spec:
   - image: "mcr.microsoft.com/dotnet/samples:aspnetapp"
     name: aspnetapp-image
     ports:
-    - containerPort: 80
+    - containerPort: 8080
       protocol: TCP
 
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@@ -24,7 +24,7 @@ spec:
   ports:
   - protocol: TCP
     port: 80
-    targetPort: 80
+    targetPort: 8080
 
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