Fix imap sensor in case of alternative empty search response

[jbouwh]

Proposed change

Fix handling an empty search response without an empty line, like icloud seems to implement.

The fix is made based on the users debug logging from #132042.

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 Imap sensor defaults to state 5 when no emails found #132042
• This PR is related to issue: #
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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