Correct nuopc.runseq for coupled compsets with NEMO

[daniele-peano]

The nuopc.runseq created in the coupled configuration with NEMO as ocean component is not working.
This creation need to be corrected.

[daniele-peano]

The OPTION2 case has been selected.
However, some discussion on OPTION1 or OPTION2 is needed.

OPTION1 -> runs prep_ocn_avg BEFORE the aoflux and ocnalb calculations
OPTION2 -> runs prep_ocn_avg AFTER the aoflux and ocnalb calculations