Voprf update (#255)

* Update to latest voprf

* Upgrade to Rust edition 2021

* Fix Clippy

* Remove all allocations

* Remove unnecessary `allow(type_alias_bounds)`

* Make all serialization infallible

* Remove self-dependency

* Update rustyline

src/tests/mock_rng.rs

@@ -5,9 +5,9 @@
 // License, Version 2.0 found in the LICENSE-APACHE file in the root directory
 // of this source tree.
 
-use alloc::vec::Vec;
 use core::cmp::min;
 use rand::{CryptoRng, Error, RngCore};
+use std::vec::Vec;
 
 /// A simple implementation of `RngCore` for testing purposes.
 ///