fix: update vscode supported max version badge in readme file

Signed-off-by: Dominik Jelinek <[email protected]>

README.md

@@ -8,7 +8,7 @@
   <a href="https://www.npmjs.com/package/@redhat-developer/page-objects"><img src="https://img.shields.io/npm/v/@redhat-developer/page-objects?color=orange&label=page%20objects&style=for-the-badge&logo=npm" alt="ExTester Page Objects"/></a>
   <a href="https://github.com/redhat-developer/vscode-extension-tester/blob/main/LICENSE"><img src="https://img.shields.io/badge/license-Apache%202-yellow.svg?style=for-the-badge&logo=appveyor" alt="License"/></a>
   </br>
-  <a href="https://code.visualstudio.com"><img src="https://img.shields.io/badge/VS_Code-1.90.x-blue?style=for-the-badge&logo=visualstudiocode" alt="Maximal supported version of VS Code"></a>
+  <a href="https://code.visualstudio.com"><img src="https://img.shields.io/badge/VS_Code-1.91.x-blue?style=for-the-badge&logo=visualstudiocode" alt="Maximal supported version of VS Code"></a>
   <a href="https://github.com/redhat-developer/vscode-extension-tester/actions/workflows/main.yml"><img src="https://img.shields.io/github/actions/workflow/status/redhat-developer/vscode-extension-tester/main.yml?label=Main%20CI&style=for-the-badge&logo=githubactions" alt="Main CI"></a>
   <a href="https://github.com/redhat-developer/vscode-extension-tester/actions/workflows/insiders.yml"><img src="https://img.shields.io/github/actions/workflow/status/redhat-developer/vscode-extension-tester/insiders.yml?branch=main&label=Insider%20CI&style=for-the-badge&logo=githubactions" alt="Insider CI"></a>
 </p><br/>