a8n: Fix PublicationEnqueued by loading all ChangesetJobs for a Campaign

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.

Created by: codecov[bot]

Codecov Report

Merging #8403 into master will not change coverage. The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #8403   +/-   ##
=======================================
  Coverage   40.57%   40.57%           
=======================================
  Files        1291     1291           
  Lines       69230    69230           
  Branches     6372     6372           
=======================================
  Hits        28093    28093           
  Misses      38531    38531           
  Partials     2606     2606

Impacted Files	Coverage Δ
...nterprise/internal/a8n/resolvers/campaign_plans.go	57.94% <100%> (ø)