change regex security for z12c

variable "safran_zone" { type = string description = "(Required) The urbassec zone of the account. If you deploy a resource on a specific safran urbasec zone, you can specify it here, otherwise, this field can be left blank" validation { condition = can(regex("^z[0-2]?[0-9]|12c$", var.safran_zone)) error_message = "The subnet zone must be in format: zi (^z[0-2]?[0-9]|12c$)." } }