Allow scaling spec to be set dynamically

[vandyliu]

Description

User wants to determine scaling_spec via variable and using tertiary operator like the following

scaling_spec = var.environment_name != "prod" ? {
    hibernation_spec = {
      override = null
      schedules = [{
        is_enabled       = true
        hibernate_at_cron = "0 22 * * *"  
        wake_at_cron     = "0 14 * * *"  
      }]
    }
  } : null

However, it does not work with the current validation.
I had to move the validation to runtime instead, which seemed to fix it. Added some integration tests as well.

🧪 Functional Testing

Added some integration tests.
Did some manual testing with the following with

1. var.environment_name == "prod"
2. var.environment_name == "dev"
3. scaling_spec.hibernation_spec.override and scaling_spec.hibernation_spec.schedule, which passes terraform plan but fails terraform apply (expected new behavior)

resource "astro_deployment" "team_1_dev_deployment" {
  name                    = "team-1-dev-deployment"
  description             = "Team 1 Dev Deployment"
  type                    = "STANDARD"
  cloud_provider          = "AWS"
  region                  = "us-east-1"
  contact_emails          = []
  default_task_pod_cpu    = "0.25"
  default_task_pod_memory = "0.5Gi"
  executor                = "CELERY"
  is_cicd_enforced        = true
  is_dag_deploy_enabled   = true
  is_development_mode     = true
  is_high_availability    = false
  resource_quota_cpu      = "10"
  resource_quota_memory   = "20Gi"
  scheduler_size          = "SMALL"
  workspace_id            = astro_workspace.team_1_workspace.id
  environment_variables   = []
  worker_queues = [{
    name               = "default"
    is_default         = true
    astro_machine      = "A5"
    max_worker_count   = 10
    min_worker_count   = 0
    worker_concurrency = 1
  }]
  scaling_spec = var.environment_name != "prd" ? {
    hibernation_spec = {
      schedules = [{
        is_enabled       = true
        hibernate_at_cron = "0 22 * * *"
        wake_at_cron     = "0 14 * * *"
      }]
    }
  } : null
}


variable "environment_name" {
  type    = string
  default = "prod"
}

📋 Checklist

• Added/updated applicable tests
• Added/updated examples in the examples/ directory
• Updated any related documentation

[vandyliu]

only worked with static scaling_spec definition