fix rustfmt issue in libstd

Author: lqd

library/alloc/src/collections/binary_heap/mod.rs

@@ -440,10 +440,7 @@ impl<T: Ord> BinaryHeap<T> {
     /// heap.push(4);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_stable(
-        feature = "const_binary_heap_constructor",
-        since = "1.80.0"
-    )]
+    #[rustc_const_stable(feature = "const_binary_heap_constructor", since = "1.80.0")]
     #[must_use]
     pub const fn new() -> BinaryHeap<T> {
         BinaryHeap { data: vec![] }