Refactor tradfri tests

[MartinHjelmare]

Breaking change

Proposed change

• Refactor the tradfri tests to not depend on integration details and make it easier to update the integration and library in the future.
• Most platforms had already been refactor previously except the light platform. To be able to finish the refactor of the light platform tests, a further refactor of the API command handling of the tests was done. The light platform can send more than a single command per service call, which required us to be able to detect more than the last sent command to calculate an appropriate state response.
• Since the library has a sans-io design, many of the mocks could be removed, after this refactor.
• The config flow tests haven't been touched in this PR. That will be done separately.

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:
• Link to documentation pull request:

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
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format 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

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  Updated and included derived files by running: python3 -m script.hassfest.
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• Untested files have been added to .coveragerc.

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[balloob]

could this become methods on the CommandStore ?

[balloob]

Could the CommandStore already be initialized with the gateway too ?

[MartinHjelmare]

I moved the functions that used the command store to the command store as methods.

[MartinHjelmare]

The command store is required by the gateway fixture, so it will always be initialized together with the mock gateway.