Update CHANGELOG for 8.33.0

[ci skip]

CHANGELOG

 # Changelog for gitlab-workhorse
 
+## v8.33.0
+
+### Added
+- Add routes for Group import via the UI
+  https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/493
+
+### Fixed
+- Gather gitlab-zip-cat/metadata stderr and log output in the current context
+  https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/498
+  Contributed by Georges-Etienne Legendre
+
 ## v8.32.1
 
 ### Security

changelogs/unreleased/fix-issue-249.yml

----
-title: Gather gitlab-zip-cat/metadata stderr and log output in the current context
-merge_request: 498
-author: Georges-Etienne Legendre
-type: fixed

changelogs/unreleased/jh-group_import_ui.yml

----
-title: Add routes for Group import via the UI
-merge_request: 493
-author:
-type: added