test plan:
This commit adds privacy level contro to content item selection requests
for the following fields:
lis_person_contact_email_primary, lis_person_name_given,
lis_person_name_full, lis_person_name_family, lis_person_sourcedid,
lis_course_offering_sourcedid, and context_label
These fields should appear for the same privacy levels as they do for a
basic lti launch. If the same tool is used in both a basic lti launch request
and a content item selection request, the above fields should either be
present on both launches or absent on both launches (depending on the
privacy level currently selected for the tool).
This commit also refactors how content item selection launches are
constructed, so it would be good to run a basic regression test on
content item selection launches in general.
fixes PLAT-2447
Change-Id: If55e9c84b3ddd91bdf700a8bbbb02d8f9a7e6e1f