feat(admin): edit assignment workflow

[CaerusKaru]

Ability to edit any of the "create assignment" workflow information.

Thoughts

• Should this share the same path/appearance as creation workflow?
• Are any of the fields untouchable at a certain point?
• Meaning: what does this mean for existing solutions?
• Should there be a validator on what can change? (ie required files after submissions received)

[CaerusKaru]

One solution to this will be to present the option to grant everyone who has submitted an extra submission for corrections (unless unlimited submissions are allowed, in which case this is moot). If any options are changed after the deadline, it's irrelevant since nothing will change.