[BUG] Restore the possibility of choosing the availability zone in AWS

[przemyslavic]

Describe the bug
In #2939 we have removed the option to choose the availability zone. Now the availability zone is selected automatically by AWS. While in most cases it is not a problem, in the case of aarch64 installation (a1 instances) there may be an issue as some instances may not be supported in the requested availability zone.

2022-02-14T14:49:22.3181271Z[31;21m14:49:22 ERROR cli.src.terraform.TerraformCommand - Error: Error launching source instance: Unsupported: Your requested instance type (a1.large) is not supported in your requested Availability Zone (eu-central-1c). Please retry your request by not specifying an Availability Zone or choosing eu-central-1a, eu-central-1b.
2022-02-14T14:49:22.3193805Z[38;21m14:49:22 INFO cli.src.terraform.TerraformCommand - 	status code: 400, request id: fad37b7b-f38e-4cf6-adc1-5207b4fc8f72


2022-02-14T14:39:46.5399721Z[31;21m14:39:46 ERROR cli.src.terraform.TerraformCommand - Error: Error launching source instance: Unsupported: Your requested instance type (a1.large) is not supported in your requested Availability Zone (eu-west-1b). Please retry your request by not specifying an Availability Zone or choosing eu-west-1a, eu-west-1c.
2022-02-14T14:39:46.5401896Z[38;21m14:39:46 INFO cli.src.terraform.TerraformCommand - 	status code: 400, request id: 8e1f31f0-dc2c-4c54-b195-3036adedddc2

Available regions:
https://aws.amazon.com/about-aws/whats-new/2019/08/amazon-ec2-a1-instances-are-now-available-in-additional-regions/

How to reproduce
Steps to reproduce the behavior:

1. execute epicli apply and try to deploy an aarch64 cluster

Expected behavior
The cluster should be deployed with no issues

Config files

...
  components:
    kafka:
      count: $(kafka_vms)
      machine: kafka-machine
    kubernetes_master:
      count: $(master_vms)
      machine: kubernetes-master-machine
    kubernetes_node:
      count: $(node_vms)
      machine: kubernetes-node-machine
    load_balancer:
      count: $(lb_vms)
      machine: load-balancer-machine
    logging:
      count: $(log_vms)
      machine: logging-machine
    monitoring:
      count: $(monitoring_vms)
      machine: monitoring-machine
    postgresql:
      count: $(postgresql_vms)
      machine: postgresql-machine
    rabbitmq:
      count: $(rabbitmq_vms)
      machine: rabbitmq-machine
    opendistro_for_elasticsearch:
      count: $(opendistro_vms)
      machine: logging-machine
    repository:
      count: 1
      machine: repository-machine
  name: $(cluster_name)
  prefix: '$(prefix)'
title: Epiphany cluster Config
---
kind: infrastructure/virtual-machine
name: kafka-machine
provider: aws
based_on: kafka-machine
specification:
  size: a1.xlarge
---
kind: infrastructure/virtual-machine
name: kubernetes-master-machine
provider: aws
based_on: kubernetes-master-machine
specification:
  size: a1.large
---
kind: infrastructure/virtual-machine
name: kubernetes-node-machine
provider: aws
based_on: kubernetes-node-machine
specification:
  size: a1.large
---
kind: infrastructure/virtual-machine
name: logging-machine
provider: aws
based_on: logging-machine
specification:
  size: a1.large
---
kind: infrastructure/virtual-machine
name: monitoring-machine
provider: aws
based_on: monitoring-machine
specification:
  size: a1.large
---
kind: infrastructure/virtual-machine
name: postgresql-machine
provider: aws
based_on: postgresql-machine
specification:
  size: a1.large
---
kind: infrastructure/virtual-machine
name: load-balancer-machine
provider: aws
based_on: load-balancer-machine
specification:
  size: a1.medium
---
kind: infrastructure/virtual-machine
name: rabbitmq-machine
provider: aws
based_on: rabbitmq-machine
specification:
  size: a1.medium
---
kind: infrastructure/virtual-machine
name: repository-machine
provider: aws
based_on: repository-machine
specification:
  size: a1.large

Environment

• Cloud provider: [AWS]
• OS: [CentOS]

epicli version: [2.0.0dev]

Additional context
Add any other context about the problem here.

---

DoD checklist

• Changelog
  • updated
  • not needed
• COMPONENTS.md
  • updated
  • not needed
• Schema
  • updated
  • not needed
• Backport tasks
  • created
  • not needed
• Documentation
  • added
  • updated
  • not needed
• Feature has automated tests
• Automated tests passed (QA pipelines)
  • apply
  • upgrade
  • backup/restore
• Idempotency tested
• All conversations in PR resolved

[przemyslavic]

✔️ Availability zones can be set again in the configuration file.