New deployment: version 313965aa2

[nwalters512]

PrairieTest version 313965aa27bb589b41df9081de0674db71bfd140 deployed just now.

Changes:

• The "Assign reservations" button on sessions is now disabled while processing, preventing accidental double-clicks that could create duplicate reservations (resolved Disable random assignment button on press #82)
• The center sessions page now shows capacity shortfall information, making it easier to identify how many additional slots are needed for exams with insufficient predicted capacity.
• Fixed a bug where the current exam popup remained visible to students after their access had ended (resolved "Current exam" popup visible after scheduled end time #99)