Remove rustc_macro test crate

tmp_test/Cargo.toml

@@ -1,9 +0,0 @@
-[package]
-name = "tmp-test"
-version = "0.1.0"
-authors = ["David Tolnay <dtolnay@gmail.com>"]
-
-[dependencies]
-serde = "0.8"
-serde_derive = { path = "../serde_derive" }
-serde_json = "0.8"

tmp_test/src/main.rs

@@ -1,16 +0,0 @@
-#![feature(rustc_macro)]
-
-#[macro_use]
-extern crate serde_derive;
-extern crate serde_json;
-
-#[derive(Serialize, Deserialize)]
-enum Macros {
-    #[serde(rename = "macros 1.1")]
-    OnePointOne,
-}
-
-fn main() {
-    let s = Macros::OnePointOne;
-    println!("{}", serde_json::to_string(&s).unwrap());
-}