fix: relay router typo for List models (#320)

via: https://platform.openai.com/docs/api-reference/models/list

router/relay-router.go

@@ -12,7 +12,7 @@ func SetRelayRouter(router *gin.Engine) {
 	modelsRouter := router.Group("/v1/models")
 	modelsRouter.Use(middleware.TokenAuth())
 	{
-		modelsRouter.GET("/", controller.ListModels)
+		modelsRouter.GET("", controller.ListModels)
 		modelsRouter.GET("/:model", controller.RetrieveModel)
 	}
 	relayV1Router := router.Group("/v1")