Update vis notebooks for levante

• change the jupyterhub kernel to "1 Python 3 (based on the module python3/2023.01)"
• remove_solutions.sh: check if given input file exists

assigned to @k204045

added 3 commits

• dac9b550 - Update remove_solutions.sh
• cb6dc374 - update remove_solutions.sh
• 8d4d6df2 - Update vis notebooks for levante

Compare with previous version

mentioned in commit b8516c00

merged