Close listening socket on graceful shutdown

[stepancheg]

Feature Request

Crates

tonic

Motivation

• listening socket will never be served, so holding it is pointless
• but it is helpful for testing behavior like reconnecting on server restart

Proposal

In the middle of here:

tonic/tonic/src/transport/server/mod.rs

Lines 768 to 770 in d4e4a2a

	}
	if graceful {

add

drop(incoming);

Alternatives

Use your own incoming and connect it to the same signal.