swarm/: Remove redundant doc strings on behaviour trait (#2634)

Signed-off-by: Carson Farmer <carson.farmer@gmail.com>

swarm/src/behaviour.rs

@@ -170,22 +170,6 @@ pub(crate) type THandlerOutEvent<THandler> =
 /// #   }
 /// # }
 /// ```
-///
-/// For users that need access to the root [`NetworkBehaviour`] implementation while processing
-/// emitted events, one can specify `#[behaviour(event_process = true)]`. Events generated by the
-/// struct members are delegated to [`NetworkBehaviourEventProcess`] implementations. Those must be
-/// provided by the user on the type that [`NetworkBehaviour`] is derived on.
-///
-/// Because these implementations are granted exclusive access to the [`NetworkBehaviour`],
-/// [blocking code](https://ryhl.io/blog/async-what-is-blocking/) in these implementations will
-/// block the entire [`Swarm`](crate::Swarm) from processing new events, since the swarm cannot progress
-/// without also having exclusive access to the [`NetworkBehaviour`]. A better alternative is to execute
-/// blocking or asynchronous logic on a separate task, perhaps with the help of a bounded channel to
-/// maintain backpressure. The sender for the channel could be included in the NetworkBehaviours constructor.
-///
-/// Optionally one can provide a custom `poll` function through the `#[behaviour(poll_method =
-/// "poll")]` attribute. This function must have the same signature as the [`NetworkBehaviour#poll`]
-/// function and will be called last within the generated [`NetworkBehaviour`] implementation.
 pub trait NetworkBehaviour: 'static {
     /// Handler for all the protocols the network behaviour supports.
     type ConnectionHandler: IntoConnectionHandler;