dev-deps: pin criterion to 0.3.4

Author: davidhewitt

Cargo.toml

@@ -32,7 +32,8 @@ serde = {version = "1.0", optional = true}
 
 [dev-dependencies]
 assert_approx_eq = "1.1.0"
-criterion = "0.3"
+# O.3.5 uses the matches! macro, which isn't compatible with Rust 1.41
+criterion = "=0.3.4"
 trybuild = "1.0.23"
 rustversion = "1.0"
 proptest = { version = "0.10.1", default-features = false, features = ["std"] }