Role/Capability: Add capability check to link_categories_meta_box

[Sukhendu2002]

Trac ticket: https://core.trac.wordpress.org/ticket/13972

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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[github-actions]

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