Patch ModifyOrderRequestToWire

[0xBoringWozniak]

This pull request includes several changes to improve the functionality and testing of order modifications in the hyperliquid package. The most important changes include adding support for spot orders in the ModifyOrderRequestToWire function, updating the BulkModifyOrders method to handle spot orders, and adding a new test for modifying orders.

Improvements to order modification functionality:

• hyperliquid/convert.go: Added support for spot orders in the ModifyOrderRequestToWire function by introducing an isSpot parameter and adjusting asset ID and decimal precision based on the order type.
• hyperliquid/exchange_service.go: Updated the BulkModifyOrders method to accept an isSpot parameter and pass it to the ModifyOrderRequestToWire function.

Additions to testing:

• hyperliquid/exchange_test.go: Added a new test function TestExchangeAPI_TestModifyOrder to verify the functionality of modifying orders, including placing a limit order, modifying it, and then canceling all orders.

Minor changes:

• hyperliquid/exchange_test.go: Added an import statement for the log package.