Fix firmware update failure

[raman325]

Proposed change

There was a bug in our code that assumed a value was not None when it was. I'm pretty sure I fixed it, but I am also not sure why it's happening or how to test it.

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Additional information

• This PR fixes or closes issue: fixes Assertion error of Z-Wave firmware update #102027
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• Link to documentation pull request:

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[cgarwood]

Tested on my dev system and is working 👍

[MartinHjelmare]

I'm pretty sure I fixed it, but I am also not sure why it's happening or how to test it.

latest_version_firmware is optional both on the entity and on the extra restore data. We need to handle that but we didn't when restoring state until this PR.

[MartinHjelmare]

To test it we have mock_restore_cache_with_extra_data which I think we can use.

[raman325]

I actually do use that mock in my tests and have one where the latest_firmware_file is None but now that I think about it more I just need to adjust the state data to show an upgrade while having the latest firmware file as none