fix: labels follows terraform convention

[AlexanderBrevig]

https://github.com/entur/terraform-google-init/blob/8b8051e07af0174d15108f763004bf58516c2868/modules/init/outputs.tf#L6-L15

output "labels" {
  description = "Labels for use on managed resources (i.e. Kubernetes resources)."
  value = {
    app         = local.app.name
    app_id      = var.app_id
    environment = var.environment
    owner       = local.app.owner
    team        = local.app.owner
  }
}