Fix nested <ul> in footnotes

[simurai]

What are you trying to accomplish?

This fixes https://github.com/github/issues/issues/2552 where a nested <ul> in a footnote would look broken.

Before	After

What approach did you choose and why?

Using inline-block for the nested <ul> makes sure the ↩︎ stays on the same line. Also fixed a bit the padding/margin.

What should reviewers focus on

An alternative would be to not allow using - (unordered list) in footnotes since footnotes are already ordered lists. But we don't really have control over the user generated markdown and omitting/removing the - (unordered list) in footnotes might also be considered as a bug? 🤔

Can these changes ship as is?

• Yes, this PR does not depend on additional changes. 🚢

[changeset-bot]

🦋 Changeset detected

Latest commit: 981d468

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/css	Patch

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[simurai]

Bellow raw Markdown and how it renders (currently still broken):

A footnote with a nested `<ul>` [^1]

[^1]: - footnote

👇

A footnote with a nested <ul> ¹

Footnotes

1. • footnote
   ↩