Fix tests after rebase

Author: estebank

src/test/ui/lint/unused/unused-async.stderr

@@ -4,12 +4,12 @@ error: unused implementer of `Future` that must be used
 LL |     foo();
    |     ^^^^^
    |
+   = note: futures do nothing unless you `.await` or poll them
 note: the lint level is defined here
   --> $DIR/unused-async.rs:2:9
    |
 LL | #![deny(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-   = note: futures do nothing unless you `.await` or poll them
 
 error: unused return value of `foo` that must be used
   --> $DIR/unused-async.rs:31:5

src/test/ui/lint/unused/unused-supertrait.stderr

@@ -2,7 +2,7 @@ error: unused implementer of `Iterator` that must be used
   --> $DIR/unused-supertrait.rs:9:5
    |
 LL |     it();
-   |     ^^^^^
+   |     ^^^^
    |
    = note: iterators are lazy and do nothing unless consumed
 note: the lint level is defined here