Avoid collision when replacing existing config entry with same unique id

[emontnemery]

Proposed change

Avoid intermittent collision when replacing existing config entry with same unique id

This is required before we can disallow config entry unique id collisions

Extracted from PR #127409

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• Dependency upgrade
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• This PR fixes or closes issue: fixes #
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[epenet]

Side note: I'm still confused that creating a config entry with the same unique id overwrites the previous config entry!
I know it's the existing behavior, but should it not at least log a warning?

[MartinHjelmare]

Is this comment still true?

# We will remove it only after the other one is set up,
# so that device customizations are not getting lost.

[emontnemery]

Is this comment still true?

# We will remove it only after the other one is set up,
# so that device customizations are not getting lost.

Fixed by #131175