Bump weatherflow4py to 0.2.20

[jeeftor]

Breaking change

Proposed change

jeeftor/weatherflow4py@v0.2.17...v0.2.20

Fixed precip icon missing in backing lib

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 # WeatherFlow Cloud - Weatherflow REST - Failed Setup, will retry 'precip_icon' #112841 (comment)
• This PR is related to issue:
• Link to documentation pull request:

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