Update extensions/ql-vscode/CHANGELOG.md

Co-authored-by: Charis Kyriakou <charisk@users.noreply.github.com>

Author: norascheuch

extensions/ql-vscode/CHANGELOG.md

@@ -1,6 +1,6 @@
 # CodeQL for Visual Studio Code: Changelog
 
-## 1.8.9 - 03 August 2023
+## 1.8.9 - 3 August 2023
 
 - Remove "last updated" information and sorting from variant analysis results view. [#2637](https://github.com/github/vscode-codeql/pull/2637)
 - Links to code on GitHub now include column numbers as well as line numbers. [#2406](https://github.com/github/vscode-codeql/pull/2406)