CSV Import does not import the "Date Updated" field

Issue Summary

When importing a CSV file to edit the Updated Date, it is not setting the date according to the CSV file.

This is reproducible on Data Center: (no)

Steps to Reproduce

1. Create a CSV file with a few dates
2. Go to the External System Import > CSV
3. Import the CSV file mapping the Date modified

Expected Results

An issue should be created/updated with the Updated date corresponding to the date of the CSV file.

Actual Results

The Updated date is not set according to the date of the CSV file.

Workaround

It seems that importing via JSON is setting the Updated date.

Update: The suggested workaround of importing via JSON appears that no longer work since it'll behave like the CSV import (Leaving the Updated date when the import action was done instead of the specified one).