Closes is the same to Opens in Quiz summary

Problem/Motivation

When you set the Start date and End date in Availability options, what will appear in the front page of the quiz is the Start date for both the Opens and Closes information.

Steps to reproduce

Create a quiz and under Availability options, set the Start date and End date. Save the Quiz and go to View tab.

Proposed resolution

Closes = End date.

Remaining tasks

User interface changes

API changes

Data model changes