Added readonly prop to make the field non-editable by typing

[NoahMLoomis]

This makes it so the user can't type in the box, the only way they can select dates is by clicking and using the datepicker

[RushiNariya]

I want to prevent the user from typing just enable date selection, and read-only prop is the option right!!, but in read mode, user should also clear the selected date, the click operation on clear icon is not working as well.