Update criterion requirement from 0.4 to 0.5 #78

Job	Run time
(Windows) Builds (x86_64-pc-windows-msvc)	1m 7s
Bench Compile (stable)	1m 30s
(OS X) Builds (aarch64-apple-ios)	2m 45s
Check (stable)	18s
(Linux) Builds (aarch64-linux-android)	2m 30s
(OS X) Builds (x86_64-apple-darwin)	2m 39s
Check (beta)	20s
Rustfmt (nightly)	17s
(Linux) Builds (x86_64-unknown-linux-musl)	1m 58s
Check (1.70.0)	27s
(Linux) Builds (wasm32-unknown-unknown)	1m 26s
Test Suite (stable)	2m 24s
Test Suite (1.70.0)	2m 36s
	20m 17s

Provide feedback