subscription data model
@type t() :: %ExRocketmq.Models.Subscription{ class_filter_mode: boolean(), code_set: [String.t()], expression_type: String.t(), sub_string: String.t(), sub_version: non_neg_integer(), tags_set: [String.t()], topic: String.t() }
@spec to_map(t()) :: %{required(String.t()) => any()}