Build an aggregation for ad rotations

[davidfischer]

Testing

• Perform an ad rotation (even manually) but hitting the API endpoint and making sure to pass rotations=2.
• Aggregate the data:

  from adserver.utils import update_previous_day_reports
  update_previous_day_reports("2024-10-18")

• Check the rotations in the admin

[ericholscher]

Simple enough. I really wish the aggregation logic was easier to abstract so we didn't have all of the complex query logic in each one, but so it goes.