Curation dates are missing from PHI-base 4.17

The curation date column in phi-base_v4-17_2024-05-01.csv is blank. In the previous version, 4.16, the column had ISO 8601 style dates. Presumably something has gone wrong with the parsing here, or the column has been cleared in error.

@martin2urban Did you use the usual pipeline to make the PHI-base 4.17 CSV file?