remove pest dependency and minimal.pest grammar file

We are no longer need this as we are no longer using the `pest` parser.

Author: gerau

Cargo.lock

@@ -23,8 +23,6 @@ serde = ["dep:serde", "dep:serde_json"]
 
 [dependencies]
 base64 = "0.21.2"
-pest = "2.1.3"
-pest_derive = "2.7.1"
 serde = { version = "1.0.188", features = ["derive"], optional = true }
 serde_json = { version = "1.0.105", optional = true }
 simplicity-lang = { version = "0.7.0" }