Update variables6.rs

Author: HariprasathGanapathiofficial

exercises/01_variables/variables6.rs

@@ -1,5 +1,5 @@
 // TODO: Change the line below to fix the compiler error.
-const NUMBER = 3;
+const NUMBER i32 = 3;
 
 fn main() {
     println!("Number: {NUMBER}");