Remove old changelog entry

Author: Benjamin Muskalla

extensions/ql-vscode/CHANGELOG.md

@@ -2,7 +2,6 @@
 
 ## [UNRELEASED]
 
-- Adjust test log output to display diffs only when comparing failed test results with expected test results. [#920](https://github.com/github/vscode-codeql/pull/920)
 - Add support for filename pattern in history view. [#930](https://github.com/github/vscode-codeql/pull/930)
 
 ## 1.5.3 - 18 August 2021