Await both the heartbeat request and shutdown channel in the heartbeat task

[teor2345]

Motivation

We don't detect cancellations when we're waiting for a response from a peer, so this could cause hangs.

zebra/zebra-network/src/peer/handshake.rs

Lines 986 to 999 in 852c5d6

	// We've reached another heartbeat interval without
	// shutting down, so do a heartbeat request.
	//
	// TODO: await heartbeat and shutdown. The select
	// function needs pinned types, but pinned generics
	// are hard (#1678)
	let heartbeat = send_one_heartbeat(&mut server_tx);
	if heartbeat_timeout(
	heartbeat,
	&mut heartbeat_ts_collector,
	&connected_addr,
	&remote_services,
	)
	.await

Specifications

Designs

Related Work

[mpguerra]

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