Issue Summary

Missing instruction for the form field of Depth of Descendants in the Children macro modal.

Steps to Reproduce

1. Edit the page
2. Add the Children macro modal.
3. In the children macro modal, Navigate to the input field section to the Depth of Descendants input field.

Screenshot

Actual Results

In the form input field of "Depth of Descendants" in the Children macro modal, there were missing instructions for the input field.  In the absence of form field information, users might incorrectly fill up the form and thus might lead to frustration as the name "Depth of Descendants" doesn't convey the information effectively as simple as "Full name", etc. 

Expected Results

Provide an instruction such as "For example, if the value is 2, the macro will display 2 levels of child pages." under the input field. 

Add an aria-describedby label to the input field and associate the id of instruction with it, so that when the screen reader enters the input field the instructions would be announced with it as well.

Workaround

Currently, there is no known workaround for this behaviour. A workaround will be added here when available