fix typo

Author: inmanturbo

resources/views/jetstream/external-iframe.blade.php

@@ -7,7 +7,7 @@ class="w-full h-full mainFrame"
             frameborder="0"
             noresize='noresize'
             scrolling='auto'
-            src="{{ $frame }}"
+            src="{{ $iframeSource }}"
             class="mainFrame">
         </iframe>
     </div>