Update parity scale codec crates

Signed-off-by: Sean Young <sean@mess.org>

Cargo.toml

@@ -45,8 +45,8 @@ sha2 = "0.9"
 ripemd160 = "0.9"
 
 [dev-dependencies]
-parity-scale-codec-derive = "1.2"
-parity-scale-codec = "1.3"
+parity-scale-codec-derive = "2.0.0"
+parity-scale-codec = "2.0.0"
 ethabi = "12.0"
 ethereum-types = "0.9"
 wasmi = "0.7"