Remove slip21

Now is unused.

Author: LeoComandini

Cargo.toml

@@ -23,7 +23,6 @@ json-contract = [ "serde_json" ]
 [dependencies]
 bitcoin = "0.30.0"
 secp256k1-zkp = { version = "0.9.2", features = [ "global-context", "bitcoin_hashes" ] }
-slip21 = "0.2.0"
 
 # Used for ContractHash::from_json_contract.
 serde_json = { version = "1.0", optional = true }

src/lib.rs

@@ -28,8 +28,6 @@
 
 /// Re-export of bitcoin crate
 pub extern crate bitcoin;
-/// Re-export of slip21 crate
-pub extern crate slip21;
 /// Re-export of secp256k1-zkp crate
 pub extern crate secp256k1_zkp;
 /// Re-export of serde crate