fix the lint problem

Signed-off-by: ZHANGWENTAI <2092913428@qq.com>

library/std/src/process.rs

@@ -2032,7 +2032,7 @@ pub fn id() -> u32 {
 /// a successful execution. In case of a failure, `libc::EXIT_FAILURE` is returned.
 ///
 /// For the reason that different runtimes have diffrent specificatons on the
-/// return value of the `main` function, this trait is likely to be available 
+/// return value of the `main` function, this trait is likely to be available
 /// only on standard library's runtime for type convenience.
 #[cfg_attr(not(test), lang = "termination")]
 #[unstable(feature = "termination_trait_lib", issue = "43301")]