Introduce testing that mirrors the OCO pipeline’s runtime use of preflight

[komish]

Borrow the pipeline’s task directly and call it in our tests, but overall this ensures that our execution of preflight (as a binary, container, etc.) does not change expectations that the pipeline has.

https://github.com/redhat-openshift-ecosystem/operator-pipelines/blob/main/ansible/roles/operator-pipeline/templates/openshift/tasks/preflight.yml

[komish]

There's now a script that runs the check operator endpoint with more environment variables, and asserts that those variables would produce specific outputs. It's not running in e2e for the moment, but we can use it for testing until we decide how we want to integrate it with openshift/release.

Unassigning this for the moment, to be picked up later.