misc: configure dependabot to use the right label

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

Motivation

Dependabot was not using the right label for security updates (#8610). This PR fixes it.

Test Plan

Test links

Deploy preview: https://deploy-preview-_____--docusaurus-2.netlify.app/

Related issues/PRs

[netlify]

✅ [V2]

Name	Link
🔨 Latest commit	2f7c180
🔍 Latest deploy log	https://app.netlify.com/sites/docusaurus-2/deploys/63d9b3d3a6f0470008876c14
😎 Deploy Preview	https://deploy-preview-8611--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]

⚡️ Lighthouse report for the deploy preview of this PR

URL	Performance	Accessibility	Best Practices	SEO	PWA	Report
/	🟠 84	🟢 97	🟢 100	🟢 100	🟢 90	Report
/docs/installation	🟠 78	🟢 100	🟢 100	🟢 100	🟢 90	Report

[slorber]

thanks