remove crate pinning for dev-dependencies

This is better done in test.sh using cargo update -p.

Author: apoelstra

Cargo.toml

@@ -24,8 +24,7 @@ actual-serde = { package = "serde", version = "1.0", optional = true }
 
 
 [dev-dependencies]
-serde_json = "<=1.0.44"
-ryu = "<1.0.5"
+serde_json = "1.0"
 elementsd = {version = "0.5.0", features=["0_21_0","bitcoind_22_0"]}
 actual-rand = { package = "rand", version = "0.8.4"}
 secp256k1 = {version = "0.22.1", features = ["rand-std"]}