Update next.md

Author: sylvestre

next.md

@@ -37,3 +37,4 @@ This file documents the pending improvements or regression:
 * https://github.com/uutils/coreutils/pull/6971
 * https://github.com/uutils/coreutils/pull/6987
 * https://github.com/uutils/coreutils/pull/6996
+* https://github.com/uutils/coreutils/pull/7013