@cubejs-client/core load method error does not contain HTTP error code

Describe the bug In @cubejs-client/core, when an errors occurs, there is no way to get errors the HTTP error code.

To Reproduce

1. Make a request using @cubejs-client/core like this

const makeQuery = async () => {
  const cubejsApi = cubejs(
    'CUBEJS-API-TOKEN',
    { apiUrl: 'http://localhost:4000/cubejs-api/v1' }
  );

  try {
    const response = await cubejsApi.load(query);
    return response.chartPivot();
  } catch (error) {
    console.log(error);
  }
}

2. error in the catch block does not contain http error code

Expected behavior error should contain the HTTP error code

Version: ^0.15.4

Additional context