Email template category to be created

• Id (string, optional): Email template category ID. Guid Id.
• Name (string, *required): The name of the email template category. It can include letters, numbers, special characters, and underscores. For example: Marketing_Emails.
• ParentId (string, optional): Parent category ID. Guid Id.
• Description (string, optional): Description of the category.
• CategoryType (string, *required): Indicates the type of category. For email templates, this should be set to 'EmailTemplate'.
• OwnerId (string, optional): Owner identifier. Guid Id.
• AccessType (string, *required): Specifies the access type for the email template category. Allowed values are: Private, Public.