Proposed title of this feature request

Enhanced alerting for Loki

What is the nature and description of the request?

Implement an AlertingRule that will alert users when a pod in a LokiStack installation is not Ready

Why does the customer need this? (List the business requirements)

When a Loki installation is not ready, logs cannot be stored.  A user needs to be alerted on this scenario so that log storage can continue as expected with minimal interruption.

List any affected packages or components.

[Please describe]