Latex broken in [TOC] both in note left navigation and [TOC] markdown

### Is this a hackmd.io issue?

- [X ] Yes, the bug happens on https://hackmd.io
- [ ] No. If it's a self-hosted CodiMD instance, please fire up the issue in the repo of CodiMD: https://github.com/hackmdio/codimd

### Read our Official tutorial

It's on https://hackmd.io/c/tutorials/

或是中文版 https://hackmd.io/c/tutorials-tw/

### What's the problem

The latex is broken in table of content

#### Current behaviour

> Screenshot (optional)

Provide steps to reproduce:

1. Go to 'hackmd'
2. Write a latex header
3. Write **[TOC]**
4. See error

If possible, create a note with reproducible content and share the link with us.

Hackmd is too lag for me to make new note

#### Expected behaviour

Should display latex as usual

#### Environment

I use HackMD on:

**Desktop**
- OS: Linux
- Browser: Google
- Browser Version: Latest

#### Additional context

NULL