Update CHANGELOG.md for 12.1.15

[ci skip]

CHANGELOG.md

@@ -2,6 +2,14 @@
 documentation](doc/development/changelog.md) for instructions on adding your own
 entry.
+## 12.1.15
+
+### Security (2 changes)
+
+- Sanitize search text to prevent XSS.
+- Fix stored XSS issue for grafana_url.
+
+
 ## 12.1.14
 - No changes.

changelogs/unreleased/security-stored-xss-using-find-file.yml

----
-title: Sanitize search text to prevent XSS
-merge_request:
-author:
-type: security

changelogs/unreleased/security-xss-grafana-url-12-4.yml

----
-title: Fix stored XSS issue for grafana_url
-merge_request:
-author:
-type: security