Update changelog for v2.1.23

Author: github-actions[bot]

CHANGELOG.md

@@ -1,6 +1,6 @@
 # CodeQL Action Changelog
 
-## [UNRELEASED]
+## 2.1.23 - 14 Sep 2022
 
 - Allow CodeQL packs to be downloaded from GitHub Enterprise Server instances, using the new `registries` input for the `init` action.  [#1221](https://github.com/github/codeql-action/pull/1221)
 - Update default CodeQL bundle version to 2.10.5. [#1240](https://github.com/github/codeql-action/pull/1240)