Extension Minor Fix

[pchae97]

currently, when a staff grants an extension to a student, the students deadline gets overridden by what the ta put. However, this causes a problem with project ec deadline; when the student who received happened to finish the project early by the ec deadline, the student won't be able to receive ec because of the overridden deadline. Could we change it so that the bakcup creation time gets set to min(extension_deadline, backup_creation_time)?

[itsnshaw]

To add to this, we should improve the extension system overall, esp for a single person to configure for many DSP students

[pchae97]

Adding on to that @itsnshaw, something I encountered a few times is auto-granting extensions to dsp students; for example, dsp students sometimes ask extensions on every single assignment, and maybe we can build in the system to give this (as opposed to the current system of ta granting each assignment extensions)