Migrate to logger.warning usage

[emmanuel-ferdman]

PR Checklist

• The commit message follows our guidelines: Code of conduct
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• Does this PR introduce a breaking change?
• Include PR in release notes?

PR Type

• Bugfix
• Feature
• Refactoring
• Build /CI
• Documentation
• Others

What is the current behavior?

The logger.warn method is deprecated so the library throws different deprecation warning:

/home/runner/work/patchwork/patchwork/patchwork/steps/ExtractModelResponse/ExtractModelResponse.py:33: DeprecationWarning: The 'warn' method is deprecated, use 'warning' instead

What is the new behavior?

This small PR migrates from logger.warn to logger.warning.

Other information

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