UniFi - Improve switch tests

[Kane610]

Breaking Change:

Description:

Related issue (if applicable): fixes #

Pull request with documentation for home-assistant.io (if applicable): home-assistant/home-assistant.io#<home-assistant.io PR number goes here>

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Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
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• Documentation added/updated in home-assistant.io

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