Update managed-environment-sharing-limits.md

[arjunmayur]

This is updating this Limit Sharing section to reflect the custom copilot and copilot extension sharing limits we are releasing at the end of September. These changes should take effect at the end of September. The copilot sharing limits described below apply to both custom copilots and copilot extensions.

[learn-build-service-prod]

Learn Build status updates of commit 821e8b8:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
power-platform/admin/managed-environment-sharing-limits.md	⚠️Warning		Details

power-platform/admin/managed-environment-sharing-limits.md

• Line 40, Column 101: [Warning: hard-coded-locale - See documentation] Link 'https://learn.microsoft.com/en-us/microsoft-copilot-studio/security-and-governance' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 40, Column 101: [Suggestion: docs-link-absolute - See documentation] Absolute link 'https://learn.microsoft.com/en-us/microsoft-copilot-studio/security-and-governance' will be broken in isolated environments. Replace with a relative link.

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