Handle meta json file for all modalities

fixes https://gitlab.ruhr-uni-bochum.de/FDM/rdm-system/antleaf-projectmanagement/-/issues/356

To generate the meta.json file for all existing CrcDatsets, do

CrcDataset.all.each do |c|
  c.handle_meta_file_on_s3
  puts "#{n}: #{c.id}"
end