Filter out banned users from Contribution Analytics

Problem: When opening the Contribution Analytics page, we look up all users who contributed to the project. Due to abuse/spam there are several deactivated/banned users who contribute to the counts (skewed results).

Task: Filter out banned users from the results.

How: Once we have the results from the DB (CH or PG), add a filter to the User query where the banned users are excluded. See the query here: https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/gitlab/contribution_analytics/data_formatter.rb#L13