chore: prepare v2.0.0-beta.19 release

[lex111]

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 #0000) and the maintainers have approved on my working plan.

Motivation

Release new beta version.

Test Plan

Preview, local test website

[netlify]

✅ [V2]

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🔨 Latest commit	a3c97c7
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[github-actions]

⚡️ Lighthouse report for the changes in this PR

URL	Performance	Accessibility	Best Practices	SEO	PWA	Report
/	🟠 59	🟢 100	🟢 92	🟢 100	🟢 90	View report
/docs/installation	🟠 83	🟢 96	🟢 100	🟢 100	🟢 90	View report

[netlify]

✅ [V2]

Name	Link
🔨 Latest commit	a71e60a
🔍 Latest deploy log	https://app.netlify.com/sites/docusaurus-2/deploys/62729b0ef712ca00082380d3
😎 Deploy Preview	https://deploy-preview-7325--docusaurus-2.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

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[github-actions]

Size Change: +2.67 kB (0%)

Total Size: 807 kB

Filename	Size	Change
website/.docusaurus/globalData.json	51.3 kB	+603 B (+1%)
website/build/assets/js/main.********.js	612 kB	+2.07 kB (0%)

ℹ️ View Unchanged

Filename	Size
website/build/assets/css/styles.********.css	105 kB
website/build/index.html	38.8 kB

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