Remove explicit pest dependency and use fastobo::syntax::pest

Author: althonos

Cargo.toml

@@ -24,7 +24,6 @@ features = ["chrono"]
 [dependencies]
 libc = "0.2.70"
 pyo3-built = "0.4.6"
-pest = "2.5.1"
 [dependencies.pyo3]
 version = "0.17.3"
 [dependencies.fastobo]

src/lib.rs

@@ -6,7 +6,6 @@ extern crate pyo3;
 #[macro_use]
 extern crate pyo3_built;
 extern crate libc;
-extern crate pest;
 #[macro_use]
 extern crate fastobo_py_derive_internal;
 extern crate fastobo_graphs;