chore: set all resource policies' allowed_roles to superadmin and admin.

[agatha197]

Modify the allowed_roles to allow creation, reading, update, and deletion of resource policies for both superadmin and admin within their respective domains.

Checklist: (if applicable)

• Milestone metadata specifying the target backport version
• Mention to the original issue
• Installer updates including:
  • Fixtures for db schema changes
  • New mandatory config options
• Update of end-to-end CLI integration tests in ai.backend.test
• API server-client counterparts (e.g., manager API -> client SDK)
• Test case(s) to:
  • Demonstrate the difference of before/after
  • Demonstrate the flow of abstract/conceptual models with a concrete implementation
• Documentation
  • Contents in the docs directory
  • docstrings in public interfaces and type annotations

[kyujin-cho]

By allowing these mutations to plain admin will there by any chance of the user crossing its domain boundary and altering settings of projects residing in other domain?