Update Changelog to 10.2.4

Author: solidnerd

Changelog.md

@@ -3,6 +3,9 @@
 This file only reflects the changes that are made in this image. Please refer to the upstream GitLab [CHANGELOG](
 https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) for the list of changes in GitLab.
 
+**10.2.4**
+- gitlab: upgrade to CE v10.2.4
+
 **10.2.3**
 - gitlab: upgrade to CE v10.2.3