Add timers to xiaomi_miio vacuum

[MarBra]

Proposed change

I like to add the list of configured timers as an attribute for a vacuum.
So that users can display them in the UI.

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)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• Link to called API from python-miio:
  https://python-miio.readthedocs.io/en/latest/miio.html#miio.vacuum.Vacuum.timer

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the [development checklist][dev-checklist]
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

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

• Documentation added/updated for [www.home-assistant.io][docs-repository]

[homeassistant]

Hi @MarBra,

It seems you haven't yet signed a CLA. Please do so here.

Once you do that we will be able to review and accept this pull request.

Thanks!

[probot-home-assistant]

This pull request needs to be manually signed off by @home-assistant/core before it can get merged.
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[probot-home-assistant]

Hey there @rytilahti, @syssi, mind taking a look at this pull request as its been labeled with a integration (xiaomi_miio) you are listed as a codeowner for? Thanks!
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[rytilahti]

The PR looks fine to me (without testing, as I don't use timers myself). This will introduce a new I/O req per update cycle, but I don't think that's a problem with these devices. When/if support for new vacuums will be introduced in the backend lib, this may need readjustments.

[rytilahti]

I think it would make sense to move this parsing to the backend library, do you agree? I think the data structure is fine, although you may want to expose the ID also, just in case if the API gets improved at some point to delete timers / toggle their state.

[MarBra]

Yes I agree. Sounds good, I will create a pull request in python-miio library.

[rytilahti]

@MarBra I just release python-miio 0.5.1, feel free to continue on this PR! :)

[MartinHjelmare]

Requesting changes to mark correct status. See above.

[rytilahti]

Looks fine for me. I'm just wondering if the API is a bit "off" when/if homeassistant needs to import pytz simply to display this information?

Btw, the PR is still marked as a draft.

[MartinHjelmare]

Looks good!

[lpfann]

This merge broke the integration for xiaomi devices for some people:
#37610

I looked into it am not sure if its an upstream bug or if this PR is buggy.
rytilahti/python-miio#759

Maybe @MarBra could look into it.