[A11y] Added tabindex="-1" to ReCAPTCHA iframes (#9069)

* [A11y] Removed tabindex from invisible Recaptcha block

* Trying tabindex=0

* Trying to set iframe tabindex=-1 using window.onload

* Verified previous change in DEV, removed unnecessary tabindex change

* Made jQuery selector specific to recaptcha iframes

Author: advay26

src/NuGetGallery/App_Code/ViewHelpers.cshtml

@@ -658,6 +658,10 @@ var hlp = new AccordionHelper(name, formModelStatePrefix, expanded, page);
             function onSubmit(token) {
                 $form.submit();
             }
+
+            window.onload = function () {
+                $('div.g-recaptcha iframe').attr({ tabindex: "-1" });
+            }
         </script>
     }
 }