@type t() :: %ExNylas.Attachment{
  content_disposition: String.t() | nil,
  content_id: String.t() | nil,
  content_type: String.t() | nil,
  filename: String.t() | nil,
  grant_id: String.t() | nil,
  id: String.t() | nil,
  is_inline: boolean() | nil,
  size: non_neg_integer() | nil
}