Create hook for adding custom CA certs

[kstrenkova]

This patch enables adding custom CA certs using a hook. The intended usage is in downstream jobs that want to add certificates into the combined-ca-bundle, e.g. internal certificates.

[openshift-ci]

Skipping CI for Draft Pull Request.
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You can still manually trigger a test run with /test all

[openshift-ci]

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[kstrenkova]

This patch is being tested here:

• https://gitlab.cee.redhat.com/ci-framework/ci-framework-jobs/-/merge_requests/1942
• https://gitlab.cee.redhat.com/ci-framework/ci-framework-testproject/-/merge_requests/1305

I have yet seen a successful run, but I would appreciate some feedback regarding the code. That is why I changed it from draft to an open PR.

[kstrenkova]

The testing on the last run was successful, search for python-octavia-tests-tempest here: https://sf.apps.int.gpc.ocp-hub.prod.psi.redhat.com/logs/522/components-integration/522d4f573f5241b59bb4e65872e80fe4/logs/controller-0/ci-framework-data/logs/openstack-k8s-operators-openstack-must-gather/namespaces/openstack/pods/tempest-tests-tempest-s00-multi-thread-testing/logs/tempest-tests-tempest-tests-runner.log

The job as a whole didn't succeed, but the python-octavia-tests-tempest plugin that was not able to be downloaded before is now downloaded correctly thanks to internal certs.

[sdatko]

Looks good to me ❤️ 🎸

[sdatko]

Sorry for misleading you with | required 😅

[sdatko]

Seemed it worked fine in testproject, we are good to have it merged IMO 🥇

[evallesp]

LGTM!