Update README.md

Author: sierpinskid

README.md

@@ -20,10 +20,6 @@
     <a href="https://github.com/GetStream/stream-chat-unity/releases/latest">
         <img alt="GitHub release (latest by date)" src="https://img.shields.io/github/v/release/GetStream/stream-chat-unity">
     </a>
-    &nbsp;
-    <a href="https://github.com/GetStream/stream-chat-unity/graphs/commit-activity">
-        <img src="https://img.shields.io/github/commit-activity/m/GetStream/stream-chat-unity" alt="GitHub commit activity">
-    </a>
     &nbsp;
 	  <a href="https://github.com/GetStream/stream-chat-unity/actions/workflows/ci.yml">
         <img src="https://github.com/GetStream/stream-chat-unity/actions/workflows/ci.yml/badge.svg?branch=develop" alt="CI">