Bugfix/2808 admin user should be able to remove admin privileges from the other admin user

[vishu-bh]

🔗 Related Issue

Closes # #2808

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📝 Summary

What does this PR do and why?

This PR fixes thes issue When an admin user tries to remove the admin privileges from the other admin user, API returns error message. It should not return an error message untill it is the last admin.

Key Changes:

• Added a new hidden form field in edit user form "disable_admin_protection". This field is sent to HTMX when edit user button is clicked.
• Added a new method to set this property to true or false based on user selection action for administrator checkbox. By default this field is None. And when an admin uncheck admin privileges from the other admin user from edit user screen, this field will update to true. And sent back to API with the request.
• In email_auth_service.py, existing check to protect_all_admins is updated to protect_all_admins if this new flag is false, otherwise skip this check.

The root cause was: There is a flag in config called 'protect_all_admins'. This flag is set to true by in configuration. Hence, it was restricting other admins to demote other admins.

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🏷️ Type of Change

• Bug fix
• Feature / Enhancement
• Documentation
• Refactor
• Chore (deps, CI, tooling)
• Other (describe below)

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🧪 Verification

Check	Command	Status
Lint suite	make lint	✅ Passed (Pylint score: 10/10)
Unit tests	make test	✅ Passed (updated unit tests with the changes)
Coverage ≥ 80%	make coverage	✅ Passed (100% for modified files, 99%+ overal

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✅ Checklist

• Code formatted (make black isort pre-commit)
• Tests added/updated for changes
• Documentation updated (if applicable)
• No secrets or credentials committed

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📓 Notes (optional)

Screenshots, design decisions, or additional context.

[ja8zyjits]

Hi @vishu-bh,

1. Please fix the linters.
2. Add your sign-off in the previous commits for all the checks here to pass,
   you may run git rebase --signoff HEAD~5