[BUG] ctx.NextOrNotFound() is running in loop

[Dexus]

Describe the bug
If you use the ctx.NextOrNotFound() function in middlewares you will run it in loop...

To Reproduce

package main

import (
	"fmt"
	"log"

	"github.com/kataras/iris/v12"
)

func main() {
	app := iris.New()
	app.Logger().SetLevel("debug")

	app.Get("/", getMiddleware1, getMiddleware2, getIndex)
	// Read the README.md before any action.
	err := app.Run(iris.Addr(":8081"))
	if err != nil {
		log.Fatal(err)
	}
}

func getIndex(ctx iris.Context) {
	ctx.Text("Page")
}

func getMiddleware1(ctx iris.Context) {
	fmt.Println("Middleware 1")
	ctx.NextOrNotFound()
}

func getMiddleware2(ctx iris.Context) {
	fmt.Println("Middleware 2")
	ctx.NextOrNotFound()
}

Expected behavior
The Middelware 2 should only run once... not in loop!

Desktop (please complete the following information):

• OS: Ubuntu 18.04.
• Iris Version: 12.1.8