Release to unstable.

debian/changelog

@@ -1,4 +1,4 @@
-cmake (3.18.4-2) UNRELEASED; urgency=medium
+cmake (3.18.4-2) unstable; urgency=medium
 
   [ Helmut Grohne ]
   * Drop unused Build-Depends: libbz2-dev and liblzma-dev. (Closes: #981135)
@@ -7,7 +7,7 @@ cmake (3.18.4-2) UNRELEASED; urgency=medium
   [ Felix Geyer ]
   * Mark cmake-data as Multi-Arch: foreign. (Closes: #973392)
 
- -- Helmut Grohne <helmut@subdivi.de>  Tue, 26 Jan 2021 16:54:47 +0100
+ -- Felix Geyer <fgeyer@debian.org>  Sun, 07 Feb 2021 10:23:34 +0100
 
 cmake (3.18.4-1) unstable; urgency=medium