Improve performance of reading many files

[stemangiola]

This part

experiment_list <- raw_data |>
            dplyr::group_by(.data[[grouping_column]]) |>
            dplyr::summarise(experiments = list(
                group_to_data_container(
                    dplyr::cur_group_id(),
                    dplyr::cur_data_all(),
                    dir_prefix,
                    features,
                    grouping_column
                )
            )) 

takes long time. Not sure if we can use zellkonverter parameters to speed this up, or using the R native package (now available)