Fix area registry indexing when there is a name collision

[arturpragacz]

Proposed change

Fix bug in area registry indexing.

If the area name was already in use, it would've raised exception, but some of the indices were already changed, leaving the state as incoherent.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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[bdraco]

Thanks @arturpragacz