Update changelog

Author: norascheuch

extensions/ql-vscode/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Add new supported source and sink kinds in the CodeQL Model Editor [#3511](https://github.com/github/vscode-codeql/pull/3511)
 - Fix a bug where the test explorer wouldn't display certain tests. [#3527](https://github.com/github/vscode-codeql/pull/3527)
+- The "model dependency" operation in the model editor can now be cancelled. [#3517](https://github.com/github/vscode-codeql/pull/3517)
 
 ## 1.12.4 - 20 March 2024