Add missing comma

Author: seratch

docs/_basic/acknowledging_requests.md

@@ -13,7 +13,7 @@ We recommend calling `ack()` right away before sending a new message or fetching
 
 ```javascript
 // Regex to determine if this is a valid email
-let isEmail = /^[\w\-\.]+@([\w\-]+\.)+[\w\-]+$/
+let isEmail = /^[\w\-\.]+@([\w\-]+\.)+[\w\-]+$/;
 // This uses a constraint object to listen for modal submissions with a callback_id of ticket_submit 
 app.view('ticket_submit', async ({ ack, view }) => {
   // get the email value from the input block with `email_address` as the block_id