fix: remove outdated badge from readme

Author: PKief

README.md

@@ -14,8 +14,6 @@
 
 ---
 
-<a href="https://github.com/material-extensions/vscode-material-icon-theme"><img src="https://img.shields.io/badge/last_built_with_vscode_theme-v5.16.0-blue" /></a>
-
 <img valign="middle" src="https://img.shields.io/chrome-web-store/v/bggfcpfjbdkhfhfmkjpbhnkhnpjjeomc?label=Version%20Available%20in%20Chrome%20Store">
 
 ### About