Before Moodle 4.3, config_plugins settings for qbank_columnsortorder
(disabledcol, enabledcol) had a value like
qbank_statistics\columns\facility_index,
qbank_statistics\columns\discriminative_efficiency, ...
In Moodle 4.3, the values are stored as
qbank_statistics\columns\facility_index-facility_index.
So updating the old values to match the new format.