iris: [BUG] when dynamic routing parameters have type judgments, cause cors problem

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Describe the bug when dynamic routing parameters have type judgments, cause cors problem

To Reproduce Steps to reproduce the behavior:

func main() {
	app := iris.New()
	app.Use(cors.AllowAll())
	app.AllowMethods(iris.MethodOptions)
	app.Delete("user/{id}", user.deleteUser) // no cors problem
	app.Delete("user/{id:uint64}", user.deleteUser) // has cors problem
	_ = app.Run(iris.Addr(":8080"))
}

Expected behavior Fix it

Desktop (please complete the following information):

• OS: MacOS