PyaroConfig from pyaerocom.io.pyaro.pyaro_config is too pedantic

[jgriesfeller]

Is your feature request related to a problem? Please describe.
PyaroConfig from pyaerocom.io.pyaro.pyaro_config is too pedantic.
Example config:

obsconfig = PyaroConfig(
            name=data_name,
            data_id=data_id,
            filename_or_obj_or_url=url,
            filters=station_filter,)

filename_or_obj_or_url can only be a string but not list of strings. It should also allow a list of strings and maybe also a list of path like objects (both!; not only path like objects since there are pyaro readers that use this differently)

Describe the solution you would like to see
allow a list of strings and a list of path like objects in addition

Additional context
This error comes up when supplying a list:

E       pydantic_core._pydantic_core.ValidationError: 1 validation error for PyaroConfig
E       filename_or_obj_or_url
E         Input should be a valid string [type=string_type, input_value=['concso4t', 'concso4c'], input_type=list]
E           For further information visit https://errors.pydantic.dev/2.9/v/string_type

test_PyerocomBinding.py:91: ValidationError