Update courses.html

Author: riverfor

docs/courses.html

@@ -15,7 +15,7 @@ <h3>Featured courses</h3>
   <br />
    <h3>More resources</h3>
      <p><a href='#' onclick='milib.openUrl("https://www.facebook.com/groups/qpython")'>Join the QPython facebook group</a></p>
-       <p><a href='#' onclick='milib.openUrl("https://join.slack.com/t/qpython/shared_invite/enQtOTI1MDY1NzM4NjU2LTljZDI3MjI0ZmZmNzIwNzAwMTU2ZDIyNGRjMTJiOTQ4MzgzY2Y3NDU5YzJjNTQ5MmM4Nzk2MGI4YWZmY2VhOTU")'>Join the QPython slack</a></p>
+       <p><a href='#' onclick='milib.openUrl("https://join.slack.com/t/qpython/shared_invite/zt-bsyw9868-nNJyJP_3IHABVtIk3BK5SA")'>Join the QPython slack</a></p>
      <p>If you use vscode development daily, I will highly recommend <a href='#' onclick='milib.openUrl("https://marketplace.visualstudio.com/items?itemName=SimaChat.sima-chat-vscode")'>Sima.ChatGPT AI Programming Assistant</a> for you, which is a great AI assistant</p>