Expose Celery Apps to PLG

[elipe17]

Description:
Now that Celery has been deployed as it's own app, we want to track it's metrics, logs, and set up alerts on failures, etc... To do this we need to add the Celery Exporter and Promtail as a subprocess on the Celery app. The Promtail subprocess should be added in the same manner that we added it to the backend app. We should also be able to deploy the Celery Exporter in the same manner.

Acceptance Criteria:
Create a list of functional outcomes that must be achieved to complete this issue

• Celery exporter and Promtail are deployed alongside all Celery apps
• Prometheus can scrape celery metrics from all environments
• Loki receives logs from the Celery apps
• Metrics/logs are queryable from Grafana
• Testing Checklist has been run and all tests pass
• README is updated, if necessary

Tasks:
TBD Pending the outcome of the "Separate Celery" ticket

• Task 1
• Task 2
• Task 3
• Run Testing Checklist and confirm all tests pass

Notes:
Add additional useful information, such as related issues and functionality that isn't covered by this specific issue, and other considerations that will be helpful for anyone reading this

• Note 1
• Note 2
• Note 3

Supporting Documentation:
Please include any relevant log snippets/files/screen shots

• Doc 1
• Doc 2

Open Questions:
Please include any questions or decisions that must be made before beginning work or to confidently call this issue complete

• Open Question 1
• Open Question 2