Add changelog note

Author: henrymercer

extensions/ql-vscode/CHANGELOG.md

@@ -5,6 +5,7 @@
 - Avoid showing an error popup when user runs a query with `@kind table` metadata. [#814](https://github.com/github/vscode-codeql/pull/814)
 - Add an option to jump from a .qlref file to the .ql file it references. [#815](https://github.com/github/vscode-codeql/pull/815)
 - Avoid opening the results panel when a database is deleted. [#831](https://github.com/github/vscode-codeql/pull/831)
+- Forward all query metadata to the CLI when interpreting results. [#838](https://github.com/github/vscode-codeql/pull/838)
 
 ## 1.4.5 - 22 March 2021