[TECHNICAL-SUPPORT] LPS-33071 Ensure that the date is entered as Custom Range only in the allowed format in Search Portlet

Hi Iliyan,

I'm sending this pull based on your comment at http://in.liferay.com/web/global.engineering/forums/-/message_boards/message/1245922?p_p_auth=wjXkt7YE#_19_message_1245958

Let me know if I made something wrong in my changes.
Thank you for reviewing.

Regards,
Tibor