fix(options3): panic when not matching to avoid false positives

Closes rust-lang#1503

exercises/options/options3.rs

@@ -13,7 +13,7 @@ fn main() {
 
     match y {
         Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
-        _ => println!("no match"),
+        _ => panic!("no match!"),
     }
     y; // Fix without deleting this line.
 }