ITVR - recreate scheduled jobs on server start

**Description:**
Currently, when the task-queue application starts, it creates scheduled jobs only if those jobs don't already exist in the database. This means that if some aspects of a job is changed (e.g. its arguments concerning timeout time, etc), one has to delete the job first in the admin console before deploying, or update the job manually in the admin console after deploying.

**Acceptance Criteria:**
Make it so that jobs are updated or recreated upon application start

**Development checklist:**
- [ ] (1) decide between updating or recreating; recreating means that the job will run once immediately upon server start, and then according to its schedule; you will also lose the number of times the job has already run. Updating preserves the number of times a job has run, but I'm not sure how caching works in this instance.

- [ ] (2) implement the decision made in (1); see scheduled_jobs.py and https://django-q.readthedocs.io/en/latest/schedules.html