Bump version to v1.5.8 (#1017)

Co-authored-by: aeisenberg <aeisenberg@users.noreply.github.com>

Author: github-actions[bot]

extensions/ql-vscode/CHANGELOG.md

@@ -1,5 +1,7 @@
 # CodeQL for Visual Studio Code: Changelog
 
+## [UNRELEASED]
+
 ## 1.5.7 - 23 November 2021
 
 - Fix the _CodeQL: Open Referenced File_ command for Windows systems. [#979](https://github.com/github/vscode-codeql/pull/979)

extensions/ql-vscode/package-lock.json

@@ -4,7 +4,7 @@
   "description": "CodeQL for Visual Studio Code",
   "author": "GitHub",
   "private": true,
-  "version": "1.5.7",
+  "version": "1.5.8",
   "publisher": "GitHub",
   "license": "MIT",
   "icon": "media/VS-marketplace-CodeQL-icon.png",