Fix test

Author: csmoe

src/test/ui/mismatched_types/closure-arg-count.stderr

@@ -2,11 +2,13 @@ error[E0593]: closure is expected to take 2 arguments, but it takes 0 arguments
   --> $DIR/closure-arg-count.rs:15:15
    |
 LL |     [1, 2, 3].sort_by(|| panic!());
-   |               ^^^^^^^ --
-   |               |       |
-   |               |       takes 0 arguments
-   |               |       help: change the closure to take and ignore the arguments: `|_, _|`
+   |               ^^^^^^^ -- takes 0 arguments
+   |               |
    |               expected closure that takes 2 arguments
+help: change the closure to take and ignore the expected arguments
+   |
+LL |     [1, 2, 3].sort_by(|_, _| panic!());
+   |                       ^^^^^^
 
 error[E0593]: closure is expected to take 2 arguments, but it takes 1 argument
   --> $DIR/closure-arg-count.rs:17:15
@@ -44,17 +46,19 @@ error[E0593]: closure is expected to take 1 argument, but it takes 0 arguments
   --> $DIR/closure-arg-count.rs:23:5
    |
 LL |     f(|| panic!());
-   |     ^ --
-   |     | |
-   |     | takes 0 arguments
-   |     | help: change the closure to take and ignore the argument: `|_|`
+   |     ^ -- takes 0 arguments
+   |     |
    |     expected closure that takes 1 argument
    |
 note: required by `f`
   --> $DIR/closure-arg-count.rs:13:1
    |
 LL | fn f<F: Fn<usize>>(_: F) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^
+help: change the closure to take and ignore the expected argument
+   |
+LL |     f(|_| panic!());
+   |       ^^^
 
 error[E0593]: closure is expected to take a single 2-tuple as argument, but it takes 2 distinct arguments
   --> $DIR/closure-arg-count.rs:26:53