disable introspection for public graph (#8773)

## Summary
- public graph used `NewDefaultServer` which configured introspection by
default
- use `New` instead and configure it the same, minus introspection
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## How did you test this change?
- sent introspection gql request to public graph locally, got
`introspection disabled` response
![Screen Shot 2024-06-17 at 9 23 04
AM](https://github.com/highlight/highlight/assets/86132398/c42f502f-6662-4e62-bc76-a6701cdef528)

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## Are there any deployment considerations?
- no, can revert if issues
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## Does this work require review from our design team?
- no
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backend/main.go

@@ -524,10 +524,23 @@ func main() {
 			r.Use(highlightChi.Middleware)
 			r.Use(public.PublicMiddleware)
 
-			publicServer := ghandler.NewDefaultServer(publicgen.NewExecutableSchema(
+			publicServer := ghandler.New(publicgen.NewExecutableSchema(
 				publicgen.Config{
 					Resolvers: publicResolver,
 				}))
+
+			publicServer.AddTransport(transport.Websocket{
+				KeepAlivePingInterval: 10 * time.Second,
+			})
+			publicServer.AddTransport(transport.Options{})
+			publicServer.AddTransport(transport.GET{})
+			publicServer.AddTransport(transport.POST{})
+			publicServer.AddTransport(transport.MultipartForm{})
+			publicServer.SetQueryCache(lru.New(1000))
+			publicServer.Use(extension.AutomaticPersistedQuery{
+				Cache: lru.New(100),
+			})
+
 			publicServer.Use(htrace.NewGraphqlTracer(string(util.PublicGraph)))
 			publicServer.SetErrorPresenter(htrace.GraphQLErrorPresenter(string(util.PublicGraph)))
 			publicServer.SetRecoverFunc(htrace.GraphQLRecoverFunc())