refactor(examples/autoscale): Autoscale example refactor

[horiagunica]

Description

• Refactored autoscale example
• Renamed example to vpc_peering_common_with_autoscale
• Example makes use of basic boostrapping using metadata
• This PR :
  • closes Example: vpc_peering_common_with_autoscale #200
  • closes Example: vpc_peering_dedicated_with_autoscale #201

Motivation and Context

• Example refactoring

How Has This Been Tested?

• Local environment and terratest idempotency tests.

Screenshots (if appropriate)

Types of changes

• New feature (non-breaking change which adds functionality)

Checklist

• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes if appropriate.
• All new and existing tests passed.

[michalbil]

This param can be moved to per autoscale deployment configuration.

[horiagunica]

Actually this parameters was left intentionally there - because otherwise this section of the code would have become a lot more complicated due to the fact that we need to iterate over autoscale variable within lb_internal module :

  backend_instance_groups = var.autoscale_regional_mig ? { for v in each.value.backends : v => module.autoscale[v].regional_instance_group_id } : merge([
    for v in each.value.backends :
    {
      for z_k, z_v in var.autoscale[v].zones :
      "${v}_${z_k}" => module.autoscale[v].zonal_instance_group_ids[z_k]
    }
  ]...)

[michalbil]

I'd propose to rename this deployment, so that it does not include "common" suffix.

[horiagunica]

Let's discuss this one during the planning.