Fix PyYAML compatibility with Python 3.10+

Update pyyaml from 5.4.1 to >=6.0 to fix build failures on Python 3.10+.
The old version had compatibility issues with newer setuptools.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

Author: semarj

requirements.txt

@@ -55,7 +55,7 @@ pytest-mock==3.6.1; python_version >= "3.6"
 pytest-watch==4.2.0
 python-dotenv==0.15.0
 pytz==2021.1; python_version >= "3.5" and python_full_version < "3.0.0" or python_full_version >= "3.4.0" and python_version >= "3.5"
-pyyaml==5.4.1; python_full_version >= "3.6.1"
+pyyaml>=6.0; python_full_version >= "3.6.1"
 regex==2021.8.3; python_version >= "3.6"
 requests==2.26.0; (python_version >= "2.7" and python_full_version < "3.0.0") or (python_full_version >= "3.6.0")
 responses==0.13.3; (python_version >= "2.7" and python_full_version < "3.0.0") or (python_full_version >= "3.5.0")