index out of range panic in v2.listItem (line 1369 in block.go file)

[chunklhit]

The below program panics:

`package main

import (
"github.com/russross/blackfriday/v2"
)

func main() {
input := ": \n\n0\n00"
blackfriday.Run([]byte(input))
}`

The Program out:

The bug was found with the help of go-fuzz.