[FEAT] Default `tiff_folder_key` parameter for ImportTiffPipeline

[mlubej]

Usually we treat the input-data folder as the default when running some pipelines, where this is the location of input data to be used in the specific pipeline.

Usually it was not the case that one had to provide specific folder keys for input-data, so perhaps I would suggest to use the input-data location as a default in cases where the tiff_folder_key parameter is not provided when running the ImportTiffPipeline. This would make the tiff_folder_key parameter optional.

IMHO since the input-data is always there and is just one, there is no need to explicitly provide it as a folder key.

[zigaLuksic]

Agreed. Prepare a MR or remind me if i forget :)