Remove num-bigint-dig dependancy

Author: Avaneesh-axiom

Cargo.toml

@@ -250,7 +250,6 @@ k256 = { version = "0.13.3", default-features = false }
 elliptic-curve = { version = "0.13.8", default-features = false }
 ecdsa = { version = "0.16.9", default-features = false }
 num-bigint = { version = "0.4.6", default-features = false }
-num-bigint-dig = { version = "0.8.4", default-features = false }
 num-integer = { version = "0.1.46", default-features = false }
 num-traits = { version = "0.2.19", default-features = false }
 ff = { version = "0.13.0", default-features = false }