Fix mqtt json light state updates using deprecated color handling

[jbouwh]

Proposed change

When a mqtt json light that is using deprecated color handling and changes from rgb color mode to color temp, this update is now processed correctly, and the light is switched from hs to color_temp color mode.

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• Dependency upgrade
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Additional information

• This PR fixes or closes issue: fixes MQTT RGB + CCT light color_mode gets overridden #104890
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• Link to documentation pull request:

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[home-assistant]

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

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[jbouwh]

With legacy color handling _attr_hs_color is used to determine the color mode, so we should reset it if we switch to color_temp:

https://github.com/home-assistant/core/pull/105283/files#diff-cf35ae315d8066bc8f6fe286f36504d3f522cf3d6c7088af1ab409756b2badc2R459-L467

[frenck]

Thanks, @jbouwh 👍