Draft: Undone

Removes the downstream gitlab trigger: in place of determining OS_TYPE before pipeline (instead of within).

trigger causes stage/job complexity and duplication, but is currently required as OS_TYPE is set within the pipeline by stages/os-type/image_inspect.py and OS_TYPE determines the OSCAP_CI_IMAGE used by a downstream stage.

An alternative is to create an OSCAP_CI_IMAGE capable of handling all OS_TYPEs ('none', 'ubi', 'ubuntu')

This change would remove two CI jobs and collapses 2 stages into 1 (parallel execution).