Bump aiowebdav2 to 0.4.3

[jpbede]

Proposed change

Bump aiowebdav2 to 0.4.3

https://github.com/jpbede/aiowebdav2/releases/tag/v0.4.3
jpbede/aiowebdav2@v0.4.2...v0.4.3

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 Settings->System->Backup can not find automatic backups saved on nextcloud using webdav #141579
• This PR is related to issue:
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

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• Tests have been added to verify that the new code works.

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  Updated by running python3 -m script.gen_requirements_all.
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