Changelog diff is:

diff --git a/Changes b/Changes
index 3eae367..9e1abc2 100644
--- a/Changes
+++ b/Changes
@@ -2,6 +2,8 @@ Revision history for Perl extension GitLab-API-v4.

 {{$NEXT}}

+0.21 2019-08-24T18:56:13Z
+
  - The release endpoint returns a 403 on an unknown tag rather than a
    404 like it should.  This condition is now detected and treated
    like a 404.