chat_notification sidekiq queue has some sort of reliance on shared storage

Problem Statement

During an evaluation of various Sidekiq Queues that are slated to be migrated into Kubernetes, it was discovered the queue chat_notification has some form of reliance on shared storage. In the case of GitLab.com this involves reading/writing data to an NFS share. We were provided the information Uses CI build trace when investigating gitlab-com/gl-infra/delivery#1059 (closed)

Due to this, the queue will not yet be migrated into Kubernetes.

Closing Criterion

• Determine where/why this queue uses shared storage
• Come up with a plan of action to remove the dependency on shared storage