Allow setting Installation Deadline by default

The app installation deadline depends on the following criteria if multiple assignments are made for the same user or device, according to this Microsoft Learn article:

• A specific deadline is chosen over the earliest possible time.

• An earlier specific deadline is chosen over a later specific deadline.

https://learn.microsoft.com/en-us/intune/intune-service/apps/apps-win32-app-management#set-win32-app-availability-and-notifications

It would be beneficial to allow editing the installation deadline without enabling application availability by default.