python-jupyter-nbformat: update to 5.6.0
python-jupyter-nbformat: update to 5.6.0

lhmouse/MINGW-packages,oscarfv/MINGW-packages,stahta01/MINGW-packages,stahta01/MINGW-packages,JPeterMugaas/MINGW-packages,JPeterMugaas/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,stahta01/MINGW-packages,lhmouse/MINGW-packages,JPeterMugaas/MINGW-packages,JPeterMugaas/MINGW-packages,stahta01/MINGW-packages,stahta01/MINGW-packages,oscarfv/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,JPeterMugaas/MINGW-packages,lhmouse/MINGW-packages,JPeterMugaas/MINGW-packages,oscarfv/MINGW-packages,stahta01/MINGW-packages