spec: force draft state on for imported_html_converter spec

not sure why this is necessary, but sometimes these specs seem to still run
with draft state off.

test plan:
- specs should pass

Change-Id: I01b23476859dce519d5858335039a6c3073c8bab
Reviewed-on: https://gerrit.instructure.com/43552
Product-Review: Jon Jensen <jon@instructure.com>
Reviewed-by: Jon Jensen <jon@instructure.com>
QA-Review: Jon Jensen <jon@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>