Fix exercice2

exercises/variables/variables2.rs

@@ -1,10 +1,8 @@
 // variables2.rs
 // Make me compile! Execute the command `rustlings hint variables2` if you want a hint :)
 
-// I AM NOT DONE
-
 fn main() {
-    let x;
+    let x: i32 = 0;
     if x == 10 {
         println!("Ten!");
     } else {