refactor: use adaptor to do relay & test

relay/channel/openai/util.go

@@ -1,12 +1,14 @@
 package openai
 
-func ErrorWrapper(err error, code string, statusCode int) *ErrorWithStatusCode {
-	Error := Error{
+import "github.com/songquanpeng/one-api/relay/model"
+
+func ErrorWrapper(err error, code string, statusCode int) *model.ErrorWithStatusCode {
+	Error := model.Error{
 		Message: err.Error(),
 		Type:    "one_api_error",
 		Code:    code,
 	}
-	return &ErrorWithStatusCode{
+	return &model.ErrorWithStatusCode{
 		Error:      Error,
 		StatusCode: statusCode,
 	}