Fix PyYaml cython error

[stan-dot]

https://pypi.org/project/PyYAML/5.4.1/

try migrating to 6.0.2

#596 (comment)

[stan-dot]

nothing in the repo seems to reference the 5.4.1 version...

[stan-dot]

Collecting PyYAML (from blueapi==0.4.5a3.dev2+gb677a55b)
  Downloading PyYAML-5.4.1.tar.gz (175 kB)
  Installing build dependencies: started
  Installing build dependencies: finished with status 'done'
  Getting requirements to build wheel: started
  Getting requirements to build wheel: finished with status 'error'
  error: subprocess-exited-with-error
  
  × Getting requirements to build wheel did not run successfully.
  │ exit code: 1
  ╰─> [54 lines of output]
      running egg_info
      writing lib3/PyYAML.egg-info/PKG-INFO
      writing dependency_links to lib3/PyYAML.egg-info/dependency_links.txt
      writing top-level names to lib3/PyYAML.egg-info/top_level.txt
      

the CI error

https://github.com/DiamondLightSource/blueapi/actions/runs/10510830504/job/29359146654

[stan-dot]

the installation with specific override in pyproject.toml into "PyYaml>=6.0.2" takes ages

[stan-dot]

and it doesn't look like it would stop on its own after 7 minutes locally

[stan-dot]

nevermind, this PR should fix it
#607 (review)