Fix int examples

Author: newpavlov

library/core/src/num/int_macros.rs

@@ -677,7 +677,7 @@ macro_rules! int_impl {
         ///
         /// ```
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_div(-1), Some(", stringify!($Max), "));")]
-        #[doc = concat!("assert_eq!(-5", stringify!($SelfT), ".checked_div(2), None);")]
+        #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").checked_div(2), None);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_div(-1), None);")]
         #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_div(0), None);")]
         /// ```