Linkable headers in storybook documentation-only MDX stories

[folz]

Is your feature request related to a problem? Please describe.
We recently converted our component library's docs to Storybook Docs. It's been mostly fantastic, but we seem to have lost the ability to link to specific sections in longform docs.

E.g. given

# Getting Started

foo

## Installation

bar

I am unable to link directly to the ## Installation subheader. Instead, I have to link to the /docs/getting-started story and tell people to scroll down to Installation.

Attempting to use "Anchors in Markdown" per https://gist.github.com/asabaylus/3071099 does not work - it renders the "heading" as a link with a literal ## in front of the link.

Describe the solution you'd like
I would like headings in documentation-only MDX to be:

1. Linkable at all (is this already possible? If so, my apologies, I was unable to find it in the docs)
2. Automatically linked (perhaps slugified?), even if I don't use the "Anchors in Markdown" syntax.

Describe alternatives you've considered
Instead of using markdown, I can use jsx like <h2 id="my-anchor"> and manually construct the link, but this is cumbersome and loses a lot of the benefits of writing docs in markdown.

I can also probably override the MDX context to use an auto-linking header component like the one I reference in "additional context" below, but I think this feature would be valuable to all users of storybook docs.

Are you able to assist bring the feature to reality?
If you point me at the relevant code I can try my best.

Additional context
I came across this gatsby plugin to autolink headers that may be useful: https://github.com/ChristopherBiscardi/gatsby-mdx/tree/master/packages/mdx-component-autolink-header

And this is how my story docs look when trying to use Anchors in Markdown

In:

## This is a heading

[## This should be a heading!](#anchor-me)

Out:

[shilman]

Closing this as a dupe to #8184 -- coming soon!