fix(utils): allow any non-boundary characters in Markdown heading ID

[Josh-Cena]

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• If this is a new API or substantial change: the PR has an accompanying issue (closes Explicit IDs for markdown headings fail to parse dots #7603) and the maintainers have approved on my working plan.

[netlify]

✅ [V2]

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[github-actions]

⚡️ Lighthouse report for the deploy preview of this PR

URL	Performance	Accessibility	Best Practices	SEO	PWA	Report
/	🔴 33	🟢 100	🟢 100	🟢 100	🟢 90	Report
/docs/installation	🟠 81	🟢 100	🟢 100	🟢 100	🟢 90	Report

[github-actions]

Size Change: 0 B

Total Size: 801 kB

ℹ️ View Unchanged

Filename	Size
website/.docusaurus/globalData.json	52.6 kB
website/build/assets/css/styles.********.css	106 kB
website/build/assets/js/main.********.js	603 kB
website/build/index.html	38.9 kB

_{compressed-size-action}

[slorber]

LGTM 👍