Add device uptime to Airobot integration

[mettolen]

Proposed change

Added device uptime sensor.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
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• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

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  Updated by running python3 -m script.gen_requirements_all.
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[joostlek]

I'm on mobile so I don't have a link, but check recent PRs for Starlink. There they use a decorator to make this happen :)

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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