Update CHANGELOG.md

Co-authored-by: Michael B. Gale <mbg@github.com>

Author: henrymercer

CHANGELOG.md

@@ -4,7 +4,7 @@ See the [releases page](https://github.com/github/codeql-action/releases) for th
 
 ## [UNRELEASED]
 
-- _Upcoming breaking change_: Add a deprecation warning for customers using CodeQL version 2.21.2 and earlier. These versions of CodeQL were discontinued on 24 September 2026 alongside GitHub Enterprise Server 3.17, and will be unsupported by the next minor release of the CodeQL Action. [#4188](https://github.com/github/codeql-action/pull/4188)
+- _Upcoming breaking change_: CodeQL version 2.21.2 and earlier were discontinued on 24 September 2026 alongside GitHub Enterprise Server 3.17, and will be unsupported by the next minor release of the CodeQL Action. Added a deprecation warning for customers using these versions of CodeQL. [#4188](https://github.com/github/codeql-action/pull/4188)
 
 ## 4.38.2 - 24 Sept 2026