Use UBI9 base image for container build

[brianwcook]

Change the container build to use UBI9 to support user access to Red Hat entitled content from the subscription service using the subscription manager tool (which wouldn't work with Rocky Linux). Since createrepo_c isn't available from the default RPM repos on UBI, install it from pypi instead. This is tied to the WIP/tech-preview RPM prefetching work.

Maintainers will complete the following section

• [ ] Commit messages are descriptive enough
• [-] Code coverage from testing does not decrease and new code is covered
• [-] Docs updated (if applicable)
• [-] Docs links in the code are still valid (if docs were updated)

Note: if the contribution is external (not from an organization member), the CI pipeline will not run automatically. After verifying that the CI is safe to run:

• approve GitHub Actions workflows by clicking a button
• approve the Red Hat Trusted App Pipeline container build by commenting /ok-to-test (as is the standard for Pipelines as Code)

[ben-alkov]

@brianwcook; For your awareness - please address CI failures.

[brianwcook]

I don't see the same build failure locally. I re-ran pip-compile with a clean venv to see if it solves the problem.

[brunoapimentel]

/ok-to-test

[brianwcook]

alright how 'bout now?

[brianwcook]

This LGTM, I only wonder if we should add a note to the commit message that the need to install subscription-manager comes from konflux-ci/build-definitions#1205.

I don't think it will be very clear to people even after #580 comes in.

added your comment and rebased again.