Created by: mrnugget
This fixes #8402 by loading all ChangesetJobs for a given Campaign/CampaignPlan to determine whether a CampaignJob has a ChangesetJob.
Before this change, the campaignJobsConnectionController would only
include the CampaignJobs that didn't have a successfully processed
ChangesetJob yet.
While publishing a Campaign that number, len(r.jobs), would go down.
Which in turn means that we would look at a smaller and smaller subset
of ChangesetJobs to determine whether the CampaignJobs we did load
have a ChangesetJob.