Update CHANGELOG.md for 12.2.1

[ci skip]

CHANGELOG.md

@@ -2,6 +2,19 @@
 documentation](doc/development/changelog.md) for instructions on adding your own
 entry.
+## 12.2.1
+
+### Fixed (3 changes)
+
+- Fix for embedded metrics undefined params. !31975
+- Fix "ERR value is not an integer or out of range" errors. !32126
+- Prevent duplicated trigger action button.
+
+### Performance (1 change)
+
+- Fix Gitaly N+1 calls with listing issues/MRs via API. !31938
+
+
 ## 12.2.0
 ### Security (4 changes, 1 of them is from the community)

changelogs/unreleased/sh-fix-issues-api-gitaly-nplusone.yml

----
-title: Fix Gitaly N+1 calls with listing issues/MRs via API
-merge_request: 31938
-author:
-type: performance

changelogs/unreleased/sh-revert-redis-cache-store.yml

----
-title: Fix "ERR value is not an integer or out of range" errors
-merge_request: 32126
-author:
-type: fixed

changelogs/unreleased/tr-param-undefined-fix.yml

----
-title: Fix for embedded metrics undefined params
-merge_request: 31975
-author:
-type: fixed