Rm mod changelog for another PR

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

Author: NobodyXu

src/changelog.rs

@@ -170,10 +170,6 @@ pub use error::Error;
 mod sftp;
 pub use sftp::{Mode, RemoteFile, Sftp};
 
-#[cfg(docsrs)]
-/// Changelog for this crate, only present in doc.
-pub mod changelog;
-
 #[cfg(feature = "process-mux")]
 pub(crate) mod process_impl;