Update model-ratio.go

修复gpt-4-1106-preview和gpt-4-0125-preview的输出倍率错误

common/model-ratio.go

@@ -202,7 +202,7 @@ func GetCompletionRatio(name string) float64 {
 		return 4.0 / 3.0
 	}
 	if strings.HasPrefix(name, "gpt-4") {
-		if strings.HasSuffix(name, "gpt-4-turbo") {
+		if strings.HasPrefix(name, "gpt-4-turbo")|| strings.HasSuffix(name, "preview") {
 			return 3
 		}
 		return 2