Add runbook on how to remove sidekiq jobs from queues based on metadata

In the past we've used something like this to clear all jobs for a certain user from a queue.

queue_name = 'project_export'
user_id = '<user id>'
dry_run = true
count = 0
queue = Sidekiq::Queue.all.find { |q| q.name == queue_name }
queue.each do |job|
  next if job.args.first.to_s != user_id.to_s
  job.delete
  count += 1
end
puts "Deleted #{count} exports"

This is based on the arguments that are passed into the worker, and requires knowledge of the code in order to be able to remove the jobs from the queue.

Now that we have metadata on the job (#9 (closed)) we could use that metadata to remove jobs.

This needs to be documented in the runbooks