We stopped generating a giant ChangeLog file in

  commit ce97c33a
  Author: Andrea Bolognani <abologna@redhat.com>
  Date:   Mon Apr 1 17:33:03 2019 +0200

      maint: Stop generating ChangeLog from git

so there is no reason to compress it anymore.
Reviewed-by: NLaine Stump <laine@laine.org>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>