Tender widget inavailability stops loading studio page

When tender_widget.js is inavailable studio page stops
loading becuase of error in the requirejs. It is
dependency in the requirejs so when it doesn't load
it cause other dependencies to stop loading.

TNL-1018
Actually in the earlier version we used document.ready where as the builtin library of domReady is the better solution to know if the page is loaded or not. So this function will add the tender_widget.js when the page is completely ready.