Adjust distance unit check in waze travel time

[epenet]

Proposed change

Adjust distance unit check in waze travel time

Linked to #80257

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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[homeassistant]

Hey there @eifinger, mind taking a look at this pull request as it has been labeled with an integration (waze_travel_time) you are listed as a code owner for? Thanks!

[epenet]

Checking/Storing the name of the unit system will stop working if we rename or add a new unit system.
It is more future-proof to check the length_unit of the unit system, even if the component still uses "imperial" terminology in the config flow.

[epenet]

Adjusted to use hass.config.units == ***

[emontnemery]

LGTM