meshcat_visualizer: force type of image paths to pathlib.Path

[abussy-aldebaran]

I got the following error while using the meshcat visualizer:

/root/miniforge3/lib/python3.12/site-packages/pinocchio/visualize/meshcat_visualizer.py:916: UserWarning: Error while loading geometry object: LThigh_0
Error message:
'str' object has no attribute 'is_absolute'

Therefore I forced the type to Path. This is coherent with the Path(img_path_abs).open("rb") two lines below.

[github-actions]

👋 Hi,
This is a reminder message to assign an extra build label to this Pull Request if needed.
By default, this PR will be build with minimal build options (URDF support and Python bindings)
The possible extra labels are:

• build_collision (build Pinocchio with coal support)
• build_casadi (build Pinocchio with CasADi support)
• build_autodiff (build Pinocchio with CppAD support)
• build_codegen (build Pinocchio with CppADCodeGen support)
• build_extra (build Pinocchio with extra algorithms)
• build_mpfr (build Pinocchio with Boost.Multiprecision support)
• build_sdf (build Pinocchio with SDF parser)
• build_accelerate (build Pinocchio with APPLE Accelerate framework support)
• build_all (build Pinocchio with ALL the options stated above)

Thanks.
The Pinocchio development team.

[nim65s]

Thanks !

[nim65s]

Can you add a little line in the CHANGELOG ?