Mean computed without weights in empirical gaussain OT

Describe the bug

in ot.gaussian the empirical means and computed with nx.mean it shoudl use weights

To Reproduce

Steps to reproduce the behavior:

  1. ...

Screenshots

Code sample

Expected behavior

Environment (please complete the following information):

  • OS (e.g. MacOS, Windows, Linux):
  • Python version:
  • How was POT installed (source, pip, conda):
  • Build command you used (if compiling from source):
  • Only for GPU related bugs:
    • CUDA version:
    • GPU models and configuration:
    • Any other relevant information:

Output of the following code snippet:

import platform; print(platform.platform())
import sys; print("Python", sys.version)
import numpy; print("NumPy", numpy.__version__)
import scipy; print("SciPy", scipy.__version__)
import ot; print("POT", ot.__version__)

Additional context