Update list of middleware for API-only in Guides

[ci skip]

guides/source/api_app.md

@@ -199,6 +199,7 @@ Choosing Middleware
 
 An API application comes with the following middleware by default:
 
+- `ActionDispatch::HostAuthorization`
 - `Rack::Sendfile`
 - `ActionDispatch::Static`
 - `ActionDispatch::Executor`
@@ -209,6 +210,7 @@ An API application comes with the following middleware by default:
 - `Rails::Rack::Logger`
 - `ActionDispatch::ShowExceptions`
 - `ActionDispatch::DebugExceptions`
+- `ActionDispatch::ActionableExceptions`
 - `ActionDispatch::Reloader`
 - `ActionDispatch::Callbacks`
 - `ActiveRecord::Migration::CheckPending`