chore: Remove rand-std from rust-btc dep

We don't use this feature anywhere.

Author: uncomputable

Cargo.toml

@@ -11,7 +11,7 @@ license = "MIT"
 repository = "https://github.com/BitVM/rust-bitcoin-script"
 
 [dependencies]
-bitcoin = { version = "0.32.5", features = ["rand-std", "serde"] }
+bitcoin = { version = "0.32.5", features = ["serde"] }
 script-macro = { path = "./macro" }
 stdext = "0.3.3"
 serde = { version = "1", features = ["derive"] }