repeater_item()
Twig function of the framework; its result is HTML and is printed without escaping.
Marks the element of an item of a repeater (Repeater), which contains the item's inner blocks. In the block
editor it becomes the inner blocks of the item being edited, or the preview of another item; on the front end
it prints nothing. Only in blocks whose render() accepts a Repeater; elsewhere it throws an exception, in
every render. The output is HTML: an attribute in renders for the block editor, otherwise ''.
Returns string