Fix tests

tests/fixture/failure/exercises/compNoExercise.rs

@@ -1,2 +1 @@
-fn main() {
-}
+fn main() {}

tests/fixture/failure/exercises/testFailure.rs

@@ -1,3 +1,5 @@
+fn main() {}
+
 #[test]
 fn passing() {
     asset!(true);

tests/fixture/failure/exercises/testNotPassed.rs

@@ -1,3 +1,5 @@
+fn main() {}
+
 #[test]
 fn not_passing() {
     assert!(false);