Gets the priority of this URL relative to other URLs on your site.
The value of the priority property lets search engines know which pages
you deem most important. Its value does not affect how your pages are
compared to pages on other sites.
Valid values range from 0.0 to 1.0.
The default priority of a page is 0.5.
This method doesn’t return any custom errors, but may return standard errors. Learn more about standard Wix errors.