Nested lists with fenced code blocks do not render correctly

Created by: rturner3

• Sourcegraph version: 3.28.0
• Platform information: Chrome 98.0.4758.109

Steps to reproduce:

1. Create a Markdown file in a Git repository that contains a nested list with a fenced code block in the nested list.

Example:

Raw Markdown

1.  Foo
    1. Bar

        ```
        Some code
        ```

    1. Baz
    
        ```
        Some more code
        ```

Expected behavior:

Markdown renders nested list items correctly with auto-incremented sub-list headers such as i. and ii., like GitHub renders it:

1. Foo

   1. Bar

      Some code

   2. Baz

      Some more code

Actual behavior:

Sourcegraph renders the nested list with incorrect indentation of the second sub-list item and does not render auto-incremented nested list item headers, such as i. and ii.. Simulated rendering:

1.  Foo
    1. Bar
        Some code
            1. Baz
        Some other code

If would like immediate help on this, please email [email protected] (you can still create the issue, but there are not SLAs on issues like there are for support requests).