docs: fix this binding in onClick .then handler with arrow functi…

…on (#2373)

docs: fix `this` binding in onClick .then handler with arrow fn

 Update the `.then()` handler in the `onClick` attribute to use an arrow function instead of a traditional `function(arg)` expression. 

This fixes the `this` binding within the lexical scope, ensuring that `this` is bound to the `button` instead of the `window` and resolving the issue.

Fixes/Closes issue  #2257

www/content/examples/confirm.md

@@ -17,7 +17,7 @@ the [`htmx:confirm`](@/events.md#htmx:confirm) event.
 <script src="https://cdn.jsdelivr.net/npm/sweetalert2@11"></script>
 <button hx-get="/confirmed" 
         hx-trigger='confirmed'
-        onClick="Swal.fire({title: 'Confirm', text:'Do you want to continue?'}).then(function(result){
+        onClick="Swal.fire({title: 'Confirm', text:'Do you want to continue?'}).then((result)=>{
             if(result.isConfirmed){
               htmx.trigger(this, 'confirmed');  
             }