Do not suggest vec macro for vecs1.rs

The solution uses the to_vec function rather than the vec macro

Author: GrimaceOfDespair

exercises/05_vecs/vecs1.rs

@@ -2,7 +2,6 @@ fn array_and_vec() -> ([i32; 4], Vec<i32>) {
     let a = [10, 20, 30, 40]; // Array
 
     // TODO: Create a vector called `v` which contains the exact same elements as in the array `a`.
-    // Use the vector macro.
     // let v = ???;
 
     (a, v)