Update azureml creation script to bypass cupy CONDA_PREFIX issue

[ncclementi]

This cupy/cupy#9777 is affecting azureml creation script as in you can't import any rapids libraries from the notebook if desired once in the rapids kernel

Until this is fixed upstream in cupy (xref: cupy/cupy#9781), we can fix it for now by modifying the startup script

python -m ipykernel install --user --name rapids --env CONDA_PREFIX "$CONDA_PREFIX"