fix: typo in DNS monitor error message (specifiy → specify)

[quantumnic]

Fixes a small typo in the DNS monitor error message shown when no resolver servers are configured.

specifiy → specify

[github-actions]

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As this is your first contribution, please be sure to check out our Pull Request guidelines.
In particular: - Mark your PR as Draft while you’re still making changes - Mark it as Ready for review once it’s fully ready
If you have any design or process questions, feel free to ask them right here in this pull request - unclear documentation is a bug too.

[Copilot]

Pull request overview

This pull request fixes a spelling mistake in an error message within the DNS monitor type. The error message is displayed when users attempt to configure a DNS monitor without specifying any resolver servers.

Changes:

• Corrected typo "specifiy" to "specify" in DNS monitor error message

[github-actions]

@redbasecap-buiss congrats on your first contribution to Uptime Kuma! 🐻
We hope you enjoy contributing to our project and look forward to seeing more of your work in the future! If you want to see your contribution in action, please see our nightly builds here.