Handle WebSocket client disconnect during prepare

[bdraco]

Proposed change

fixes #120825

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as it has been labeled with an integration (websocket_api) you are listed as a code owner for? Thanks!

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[elupus]

Looks alright.

[bdraco]

Thanks