Fix access note for Microsoft 365 admin center

[cwanja-msft]

Updated note to include link for accessing Microsoft Admin Center settings.

[learn-build-service-prod]

Learn Build status updates of commit 6fc64c4:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
power-platform/admin/allow-llm-generative-responses.md	⚠️Warning		Details

power-platform/admin/allow-llm-generative-responses.md

• Line 22, Column 44: [Warning: hard-coded-locale - See documentation] Link 'https://learn.microsoft.com/en-us/copilot/microsoft-365/connect-to-ai-models' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 22, Column 44: [Suggestion: docs-link-absolute - See documentation] Absolute link 'https://learn.microsoft.com/en-us/copilot/microsoft-365/connect-to-ai-models' will be broken in isolated environments. Replace with a relative link.

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[learn-build-service-prod]

Learn Build status updates of commit c4912ca:

✅ Validation status: passed

File	Status	Preview URL	Details
power-platform/admin/allow-llm-generative-responses.md	✅Succeeded

For more details, please refer to the build report.