Document production cron

[jefftriplett]

          > We can adjust cron in a new PR.

Do you mean the cron schedule?

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How do we setup cron jobs on the current production servers? I don't see any references to it on the codebase other than this:

djangopackages/fabfile.py

Lines 127 to 131 in 024ece9

	def cron():
	with env.cd(env.project_dir):
	docker_compose("run django-a python manage.py import_classifiers")
	docker_compose("run django-a python manage.py import_products")
	docker_compose("run django-a python manage.py import_releases")

Do we set this up manually on production server by modifying the crontab file?

Originally posted by @saadmk11 in #1012 (comment)