Changes to Get Membership Tiers

added the new all_members_birthday_credit enum value to the items/user_credit_rules/items/rule_type response property for the response status 200

added the new specific_tiers_birthday_credit enum value to the items/user_credit_rules/items/rule_type response property for the response status 200

added the enum value user_coupon_rules to the property items/ of the query request parameter include_fields[]

added the optional property items/member_point_rules/items/validity_days to the response with the 200 status

added the optional property items/user_coupon_rules to the response with the 200 status