Uploading the tools_STM_scan causes a circular import

[Raff-physics]

There is a circular import when uploading the aiida_kkr.tools.tools_STM_scan, or even when importing aiida_kkr.tools.combine_imps

A workaround this issue is to import combine_imps_wc from aiida_kkr.workflows before calling the other modules.

A snippet is provided to reproduce the error:

from aiida_kkr.tools.tools_STM_scan import STM_pathfinder
# for host remote you will need the remote folder of a host calculation
vec, mat = STM_pathfinder(host_remote)

from aiida_kkr.tools.combine_imps import get_scoef_single_imp
from aiida_kkr.workflows import combine_imps_wc