add time feature to tokio dependency

[robjtede]

time functions are used here

redis-rs/redis/src/cluster_async/mod.rs

Lines 301 to 302 in 3cacd8b

	#[cfg(feature = "tokio-comp")]
	sleep: Box::pin(tokio::time::sleep(sleep_duration)),

[jaymell]

Thanks! Did you intend to leave this as a draft?

[jaymell]

Much appreciated!