Fixed CHANGELOG.md after 2.4.13 release.

Author: atollk

CHANGELOG.md

@@ -8,6 +8,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Unreleased
 
+### Changed
+
+- FTP servers that do not support the MLST command now try to use the MDTM command to
+  retrieve the last modification timestamp of a resource. 
+  Closes [#456](https://github.com/PyFilesystem/pyfilesystem2/pull/456).
+
 
 ## [2.4.13] - 2021-03-27
 
@@ -33,9 +39,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   test suites.
 - `FSTestCases` now builds the large data required for `upload` and `download` tests only
   once in order to reduce the total testing time.
-- FTP servers that do not support the MLST command now try to use the MDTM command to
-  retrieve the last modification timestamp of a resource. 
-  Closes [#456](https://github.com/PyFilesystem/pyfilesystem2/pull/456).
 - `MemoryFS.move` and `MemoryFS.movedir` will now avoid copying data.
   Closes [#452](https://github.com/PyFilesystem/pyfilesystem2/issues/452).
 - `FS.removetree("/")` behaviour has been standardized in all filesystems, and