add bicep templates/instructions for 3P observability setup

[princjef]

Adds the following bicep templates which are used to set up various aspects of 3P observability for customers and adds documentation for how to install/uninstall them and set up additional 3P observability configuration:

• observability.bicep - creates shared observability resources (Grafana, Azure Monitor, etc.)
• cluster.bicep - creates cluster-specific resources that connect it to the shared observability resources. has two sub-deployments within it:
  • cluster-dataCollectionRules.bicep - creates data collection rules for the cluster
  • cluster-recordingRules.bicep - creates recording rules for the cluster
• observability-full.bicep - creates everything from the observability.bicep and cluster.bicep files in a single deployment for ease of use on first run