Add tokio taskname registration for use in tokio-console #634

Job	Run time
Documentation	20s
Lints	46s
Build Examples	2m 33s
Minimum Supported Rust Version	31s
Build (aarch64-unknown-linux-gnu)	52s
Semantic Versioning	14s
Build (x86_64-pc-windows-gnu)	1m 16s
Test Suite	3m 54s
Build (x86_64-unknown-linux-gnu)	3m 55s
Memory leaks	4m 8s
Minimal Dependency Versions	21s
Minimal Dependency Versions (MSRV)	38s
Publish version	0s
	19m 28s

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