Update changelog for 2.11.5

Author: cklin

CHANGELOG.md

@@ -16,6 +16,17 @@
      checklist for a CLI release, you can edit here. But then
      you know what to do).
 -->
+
+## Release 2.11.5 (2022-12-07)
+
+### Bugs Fixed
+
+- Fixed a bug where it was not possible to run queries in CodeQL query packs for C#
+  that use the legacy `libraryPathDependencies` property in their `qlpack.yml` file.
+  The associated error message complained about undefined extensional predicates.
+
+- Fixed a bug that could cause log summary generation to fail in vscode.
+
 ## Release 2.11.4 (2022-11-24)
 
 ### New features