UFAL/local.files.size is 0 but there's a file with non zero size

[Paurikova2]

ufal/clarin-dspace#1241

[kuchtiak-ufal]

The script for fixing the incorrect files metadata is here:
ufal/clarin-dspace#1241

But there is still an issue why this invalid files metadata were created during the migration.
(should be fixed in migration process)