Moving array access for captcha _.isEmpty check

When upgrading to 2.3.6 from 2.3.5-p2, a new CAPTCHA zone "payment_processing_request" is added.

If a customer has an existing session (from 2.3.5-p2 or prior), and tries to access checkout with their existing session data, checkout will fail to load because the check to see if captchaData[formId] exists is not a valid function call.
_.isEmpty() only returns a boolean value, so it cannot be enumerated like an array. Array access syntax has been moved in to the check, rather than outside it.

Author: MellenIO

app/code/Magento/Captcha/view/frontend/web/js/view/checkout/defaultCaptcha.js

@@ -56,7 +56,7 @@ define([
          */
         checkCustomerData: function (formId, captchaData, captcha) {
             if (!_.isEmpty(captchaData) &&
-                !_.isEmpty(captchaData)[formId] &&
+                !_.isEmpty(captchaData[formId]) &&
                 captchaData[formId].timestamp > captcha.timestamp
             ) {
                 if (!captcha.isRequired() && captchaData[formId].isRequired) {