- Set `ChannelBindingAdapter`'s channel resolver to use
`BinderAwareChannelResolver`.
- Previously the runtime `Binder` singleton object was lazily
instantiated. But the instantiation actually happened at the constructor
of BinderAwareRouterBeanPostProcessor itself. Hence, removed the lazy
instantiation of the Binder object. Also, I don't see any impact of
creating the `Binder` object at the time of BeanPostProcessor
creation.