chore: remove quiz4

exercises/quiz4.rs

@@ -1,23 +0,0 @@
-// quiz4.rs
-// This quiz covers the sections:
-// - Modules
-// - Macros
-
-// Write a macro that passes the quiz! No hints this time, you can do it!
-
-// I AM NOT DONE
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_my_macro_world() {
-        assert_eq!(my_macro!("world!"), "Hello world!");
-    }
-
-    #[test]
-    fn test_my_macro_goodbye() {
-        assert_eq!(my_macro!("goodbye!"), "Hello goodbye!");
-    }
-}

info.toml

@@ -965,14 +965,6 @@ scratching the surface of what you can do with Rust's macros. For a more
 thorough introduction, you can have a read through the little book of Rust
 macros: https://veykril.github.io/tlborm/"""
 
-# TEST 4
-
-[[exercises]]
-name = "quiz4"
-path = "exercises/quiz4.rs"
-mode = "test"
-hint = "No hints this time ;)"
-
 #  CLIPPY
 
 [[exercises]]