Issue 1366 - Slack integrations [ Siblings Check 2021]

[PedroFonsecaDEV]

Issue This PR Addresses

Type of Change

• Bugfix: Change which fixes an issue
• New Feature: Change which adds functionality
• Documentation Update: Change which improves documentation
• UI: Change which improves UI

Description

I think is time to test this PR on our servers. I created a Slack workspace to test it so all the messages will be posted there until we have sure that everything is working well.

This PR is part of the solution of #1366.
Siblings Checkers: DEV and PROD checking each other periodically.

We also have an internal checker:
Slack Integration: Docker Events

Checklist

• Quality: This PR builds and passes our npm test and works locally
• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not (if applicable)
• Documentation: This PR includes updated/added documentation to user exposed functionality or configuration variables are added/changed or an explanation of why it does not(if applicable)