backpopulate_mitxonline_data raising error on missing enrollment start date for program

[sentry-io]

Sentry Issue: OPEN-8ZR

KeyError: 'enrollment_start'
(7 additional frame(s) were not displayed)
...
  File "manage.py", line 14, in <module>
    execute_from_command_line(sys.argv)
  File "course_catalog/management/commands/backpopulate_mitxonline_data.py", line 39, in handle
    task.get()

[mbertrand]

@pdpinch is it legitimate for a mitxonline course/program to not have an enrollment start/end date, or is this just a case of bad data?