Use shorthand device info attribute for roomba

[jpbede]

Proposed change

Avoid using intermediate properties to carry data for the device_info property function, instead set the device info in __init__ via _attr_device_info.

These properties don't seem to be used anywhere else.

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• Dependency upgrade
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @pschmitt, @cyr-ius, @shenxn, @Xitee1, mind taking a look at this pull request as it has been labeled with an integration (roomba) you are listed as a code owner for? Thanks!

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[bdraco]

This isn't so great, but its an existing problem so ok for now

[bdraco]

tested 👍