Note `Provider::new_sync()` in `Provider::new()` doc. #386

Job	Run time
no_std	36s
build (ubuntu, stable, locked, true)	23m 23s
incremental-mutants	0s
build (windows, stable, locked, false)	42m 17s
miri	1m 41s
build (macos, stable, locked, false)	26m 58s
build (ubuntu, nightly, locked, false)	5m 27s
build (ubuntu, beta, locked, false)	22m 40s
build (ubuntu, stable, latest, false)	11m 8s
build (ubuntu, stable, minimal, false)	22m 18s
deploy	6s
features	25m 11s
fuzz	15m 2s
	3h 16m 47s

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