Irrigation example notebook fails to parse config file

The https://github.com/eWaterCycle/ewatercycle/blob/main/docs/examples/Irrigation.ipynb notebook has
```python
merrimack_parameterset = ewatercycle.parameter_sets.ParameterSet(
name="custom_parameter_set",
directory="/mnt/data/examples/technical_paper/pcr-globwb/input",
config="./pcrglobwb_merrimack.ini",
target_model="pcrglobwb",
doi="10.5281/zenodo.1045339",
supported_model_versions={"setters"},
)
```

To run on snellius I adjusted the directory argument to `/projects/0/wtrcycle/parameter-sets/pcrglobwb_global` . After that the nb still failed with
```python
NoSectionError: No section: 'globalOptions'
```
The config file it tried to read was `/projects/0/wtrcycle/parameter-sets/pcrglobwb_merrimack.ini`, which does not exist.
I expected the config file to searched for at `/projects/0/wtrcycle/parameter-sets/pcrglobwb_global/pcrglobwb_merrimack.ini` or `/home/verhoes/ewatercycle/docs/examples/pcrglobwb_merrimack.ini` (relative to my current working directory).

As workaround I made the config argument a absolute path.

Can the config argument in the irrigation example be adjusted to either be inside the parameterset directory or use an absolute path?