Update changelog for 16.7.7

[ci skip]

Author: GitLab Release Tools Bot

CHANGELOG.md

@@ -112,6 +112,12 @@ No changes.
 - [Stop building for OpenSUSE 15.4](gitlab-org/omnibus-gitlab@d6d3933486f4b6d86320652882faa0019dc1aae7) ([merge request](gitlab-org/omnibus-gitlab!7331))
 - [Stop sidekiq namespaced probe for gitlab-exporter](gitlab-org/omnibus-gitlab@ff1df765a218a7b29ad6c4a9ccd6b091a2a10bfe) ([merge request](gitlab-org/omnibus-gitlab!7237))
 
+## 16.7.7 (2024-03-06)
+
+### Security (1 change)
+
+- [Mattermost Security Updates February 14, 2024](gitlab-org/security/omnibus-gitlab@49f6b98dc7f08b3f1d5d2bad6c629bffc77976e6) ([merge request](gitlab-org/security/omnibus-gitlab!417))
+
 ## 16.7.6 (2024-02-20)
 
 No changes.