update:Use the Milliseconds method of duration to get the number of milliseconds (#3285)

Co-authored-by: Kevin Wan <wanjunfeng@gmail.com>

tools/goctl/api/gogen/genroutes.go

@@ -129,7 +129,7 @@ rest.WithPrefix("%s"),`, g.prefix)
 				return fmt.Errorf("timeout should not less than 1ms, now %v", duration)
 			}
 
-			timeout = fmt.Sprintf("\n rest.WithTimeout(%d * time.Millisecond),", duration/time.Millisecond)
+			timeout = fmt.Sprintf("\n rest.WithTimeout(%d * time.Millisecond),", duration.Milliseconds())
 			hasTimeout = true
 		}