Add Xiaomi Miio light config flow

[starkillerOG]

Breaking change

The Xiaomi Miio Light platform now uses Config Flow, the old yaml config is imported to a Config Entry, please remove the yaml config once you see the Loading Xiaomi Miio Light via platform setup is deprecated. Please remove it from your configuration. warning in the log.

The brand and brand_sleep attributes were renamed to band and band_sleep.

Proposed change

Add config flow for the Xiaomi Miio Light platform

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

Example entry for configuration.yaml:

Config flow

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request: Add Xiaomi Miio Light config flow home-assistant.io#16782

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
• 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

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

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• Untested files have been added to .coveragerc.

The integration reached or maintains the following Integration Quality Scale:

• No score or internal
• 🥈 Silver
• 🥇 Gold
• 🏆 Platinum

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[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 an integration (xiaomi_miio) you are listed as a codeowner for? Thanks!
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[starkillerOG]

@MartinHjelmare could you also revieuw/merge this PR (since you also did all other Miio config flows)?

[MartinHjelmare]

Please resolve the merge conflict.

[starkillerOG]

@MartinHjelmare merge conflict has been resolved.

[MartinHjelmare]

Looks good!

[starkillerOG]

@MartinHjelmare you also already approved this PR, can you also merge this one?

[MartinHjelmare]

Yes, please solve the merge conflict and I'll merge.

[starkillerOG]

@MartinHjelmare just resolved the merge conflict.

[starkillerOG]

@MartinHjelmare all tests have passed