fix: Remove forced DOWN status in group monitor

[MayMeow]

Summary

My earlier changes to the group monitor explicitly override the status to 'DOWN' when the children are down which was not a problem with basic kind ofgroup monitor but causing problem when monitor is upside-down type.

I removed the line in my earlier code that casues the issue.

• Relates to Fix Group monitors to send notification after reaching maximum retires count #6286
• Resolves Upside Down Mode Not Working for Group Monitors Anymore #6996

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• ⚠️ If there are Breaking change (a fix or feature that alters existing functionality in a way that could cause issues) I have called them out
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Screenshots for Visual Changes

The monitor behavior afeter changes:

I was not sure about behavior - especially if It should go trough "pending" state before the change when there is bigger retires number so I compare them with my instance Version: 1.23.16 that running in my lab and it looks OK to me. Screenshot bellow is here just for compare.

[Copilot]

Pull request overview

This pull request fixes a critical bug with upside-down group monitors introduced in PR #6286. The issue was that group monitors in upside-down mode were incorrectly showing DOWN status even when they should show UP.

Changes:

• Removes forced DOWN status assignment in GroupMonitorType.check() that prevented upside-down mode from working correctly
• Allows the monitor's retry logic and status flipping mechanism to handle the status properly

[louislam]

Thanks, I think it works.