Prompts the current visitor to log in as a site member.
The promptLogin() function returns a Promise that resolves
when the login has completed.
If the visitor cancels the form without logging in, the Promise is rejected.
The promptLogin() function cannot be called before the page is ready.
Notes:
The APIs in wix-members-frontend are only partially functional when previewing your site.
View a published version of your site to see their complete functionality.
The APIs in wix-members-frontend can only be used once the page has loaded. Therefore,
you must use them in code that is contained in or is called from the
onReady() event handler or any element event handler.
If you return or await the promptLogin() function
when calling from onReady(), the page will be prevented from loading.
To handle the resolved promise, use .then() and .catch().
The options that determine how the login dialog box appears.