Update CHANGELOG for release.

Author: jcreedcmu

extensions/ql-vscode/CHANGELOG.md

@@ -1,7 +1,8 @@
 # CodeQL for Visual Studio Code: Changelog
 
-## 1.1.1
+## 1.1.1 - 23 March 2020
 
+- Fix quick-query not working on `.qll` files.
 - Add new command in query history view to view the log file of a
   query.
 - Request user acknowledgment before updating the CodeQL binaries.