Rewrite some queries in views to use Django Models

[jonespm]

We may want to try to clean up these queries to use the Django Models directly which could improve readability and get rid of SQL from this code.

Since this isn't the highest priority it's going in the backlog.

But for this query it would probably be something like this

query_results = ResourceAccess.objects.filter(
    access_time__gt=start_time,
    access_time__lt=end_time,
    course_id=course_id
).values(
    'resource_id',
    'resource__resource_type',
    'resource__name',
    'user__current_grade',
    'user_id'
).filter(
    user__course_id=course_id,
    user__enrollment_type=enrollment_type
)

https://github.com/tl-its-umich-edu/my-learning-analytics/blob/0baa298eeef3479a5f6029f2fd09cdee26356c8f/dashboard/views.py#L301