Gets the wix-widget module scoped to an inner (nested) widget.
The getNestedWidget() function lets you use wix-widget functions on inner (nested) widgets. It receives a selector of an inner widget and returns a promise that resolves with an object representing the scope of the inner widget.
A string of one or more nested widget selectors, which can include a few levels of nesting from outer to inner, separated by spaces. For example: ("#nestedWidget1"), or ("#nestedWidget1 #nestedWidget2").