Rollup merge of rust-lang#142402 - sorairolake:remove-blank-line, r=workingjubilee

chore(doctest): Remove redundant blank lines

Remove redundant leading blank lines from doctests of [`iN::cast_unsigned`](https://doc.rust-lang.org/std/primitive.i32.html#method.cast_unsigned), [`slice::escape_ascii`](https://doc.rust-lang.org/std/primitive.slice.html#method.escape_ascii) and [`u8::escape_ascii`](https://doc.rust-lang.org/std/primitive.u8.html#method.escape_ascii).

Author: matthiaskrgr

library/core/src/num/int_macros.rs

@@ -239,7 +239,6 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        ///
         #[doc = concat!("let n = -1", stringify!($SelfT), ";")]
         ///
         #[doc = concat!("assert_eq!(n.cast_unsigned(), ", stringify!($UnsignedT), "::MAX);")]

library/core/src/num/mod.rs

@@ -1053,7 +1053,6 @@ impl u8 {
     /// # Examples
     ///
     /// ```
-    ///
     /// assert_eq!("0", b'0'.escape_ascii().to_string());
     /// assert_eq!("\\t", b'\t'.escape_ascii().to_string());
     /// assert_eq!("\\r", b'\r'.escape_ascii().to_string());

library/core/src/slice/ascii.rs

@@ -128,7 +128,6 @@ impl [u8] {
     /// # Examples
     ///
     /// ```
-    ///
     /// let s = b"0\t\r\n'\"\\\x9d";
     /// let escaped = s.escape_ascii().to_string();
     /// assert_eq!(escaped, "0\\t\\r\\n\\'\\\"\\\\\\x9d");