Added Sidebar toggle shortcut in keyboard shortcut overlay

Author: shakti97

client/modules/IDE/components/KeyboardShortcutModal.jsx

@@ -74,6 +74,12 @@ function KeyboardShortcutModal() {
         </span>
         <span>Turn off Accessible Output</span>
       </li>
+      <li className="keyboard-shortcut-item">
+        <span className="keyboard-shortcut__command">
+          {metaKeyName} + B
+        </span>
+        <span>Toggle Sidebar</span>
+      </li>
     </ul>
   );
 }