Fix formatting: join let bindings, remove extra blank line

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Samuelsills

library/alloc/src/sync.rs

@@ -4705,14 +4705,12 @@ mod verify {
 
     #[kani::proof]
     fn verify_new_uninit_in() {
-        let _a: Arc<MaybeUninit<i32>, Global> =
-            Arc::new_uninit_in(Global);
+        let _a: Arc<MaybeUninit<i32>, Global> = Arc::new_uninit_in(Global);
     }
 
     #[kani::proof]
     fn verify_new_zeroed_in() {
-        let a: Arc<MaybeUninit<i32>, Global> =
-            Arc::new_zeroed_in(Global);
+        let a: Arc<MaybeUninit<i32>, Global> = Arc::new_zeroed_in(Global);
         let a = unsafe { a.assume_init() };
         assert!(*a == 0);
     }
@@ -4861,7 +4859,6 @@ mod verify {
         assert!(*a == 0);
     }
 
-
     #[kani::proof]
     fn verify_from_str() {
         let a: Arc<str> = Arc::from("hello");