[Metricbeat] Add integration tests for Azure

[narph]

Current azure integration tests expect an azure environment already setup and having the azure resources up and running.
The goal of this enhancement is to build a solution in order to deploy these specific azure resources, check health, gather and test the metrics corresponding to each azure metricset and remove the resources (with terraform, investigate pulumi).

Current azure metricsets to implement this solution:

• compute_vm
• compute_vm_scaleset
• container_instance
• container_registry
• container_service
• database_account
• monitor
• storage

[elasticmachine]

Pinging @elastic/integrations (Team:Integrations)

[elasticmachine]

Pinging @elastic/integrations-platforms (Team:Platforms)

[botelastic]

Hi!
We just realized that we haven't looked into this issue in a while. We're sorry!

We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1.
Thank you for your contribution!