Changes to Get All Isolated Margin Symbol(USER_DATA)

added the new required query request parameter symbol

for the query request parameter recvWindow, the format changed from no format to int64

for the query request parameter timestamp, the format changed from no format to int64

the response property code became required for the status 400

the response property code became required for the status 401

the response property items/base became required for the status 200

the response property items/isBuyAllowed became required for the status 200

the response property items/isMarginTrade became required for the status 200

the response property items/isSellAllowed became required for the status 200

the response property items/quote became required for the status 200

the response property items/symbol became required for the status 200

the response property msg became required for the status 400

the response property msg became required for the status 401