Remove example/serial_derive.

example/serial_derive/.gitignore

@@ -1,2 +0,0 @@
-target/*
-Cargo.lock

example/serial_derive/Cargo.toml

@@ -1,11 +0,0 @@
-[package]
-name = "serial_derive"
-version = "0.1.0"
-edition = "2021"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-darkfi = {path = "../../", features = ["util"]}
-
-[workspace]

example/serial_derive/src/main.rs

@@ -1,14 +0,0 @@
-use darkfi::util::serial::{
-    serialize, Decodable, Encodable, SerialDecodable, SerialEncodable, VarInt,
-};
-
-#[derive(SerialEncodable)]
-enum Test {
-    Type1(u32),
-    Type2,
-    Type3,
-}
-
-fn main() {
-    println!("Hello, world!");
-}