docs: fix localhost url without link

[slorber]

Minor docs change because my new visual diff toy reports a diff in the MDX 2 PR (#8288)

This change permits me to avoid excluding the whole /docs/installation URL from the visual diff

MDX 2 + GFM will autolink while MDX 1 does not.

https://app.argos-ci.com/slorber/docusaurus-visual-tests/builds/10/40206528

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[github-actions]

⚡️ Lighthouse report for the deploy preview of this PR

URL	Performance	Accessibility	Best Practices	SEO	PWA	Report
/	🟠 80	🟢 97	🟢 100	🟢 100	🟢 90	Report
/docs/installation	🟠 78	🟢 100	🟢 100	🟢 100	🟢 90	Report

[ilg-ul]

Just curious, the GitHub markdown syntax <http://localhost:3000> is not accepted by MDX?

[github-actions]

Size Change: 0 B

Total Size: 952 kB

ℹ️ View Unchanged

Filename	Size
website/.docusaurus/globalData.json	86.2 kB
website/build/assets/css/styles.********.css	113 kB
website/build/assets/js/main.********.js	712 kB
website/build/index.html	41.1 kB

_{compressed-size-action}

[slorber]

Just curious, the GitHub markdown syntax <http://localhost:3000> is not accepted by MDX?

When in doubt, use the playground. MDX tries to align with GFM so it should, but I don't know all the edge cases and bugs it can have

[ilg-ul]

When in doubt, use the playground.

oops! it'll take me some time to get used to it. :-(

I checked and it fails with:

error  Unexpected character `/` (U+002F) before local name, expected a character that can start a name, such as a letter, `$`, or `_` (note: to create a link in MDX, use `[text](url)`)  unexpected-character  micromark-extension-mdx-jsx