Description of problem:

The `A MachineOSConfig with an unfinished build can be re-build` OnClusterBuild test is flaky and has a 7-day pass rate below 95%.

Version-Release number of selected component (if applicable):

Seen in 4.20, possible in other versions.

How reproducible:

Failures happen intermittently, I have not been able to reproduce locally.

Steps to Reproduce:

See the following test runs to see examples of the test failures:

• e2e-metal-ipi-ovn-ipv4-mco-disruptive-techpreview
• e2e-metal-ipi-ovn-ipv6-mco-disruptive-techpreview
• e2e-metal-ipi-ovn-ipv6-mco-disruptive-techpreview
• e2e-vsphere-mco-disruptive-techpreview

Actual results:{}

The `77782-A MachineOSConfig with an unfinished build can be re-build` test fails with the following error:

fail [github.com/openshift/machine-config-operator/test/extended/mco_ocb.go:423]: OCL was disabled in ci-op-c0gfkn94-40d0b-p8xl2-worker-0-44szr but the OCL image is still used in %!s(MISSING)
Expected
    <string>: image-registry.openshift-image-registry.svc:5000/openshift-machine-config-operator/ocb-worker-image@sha256:97edc354a21123b870717ac0796a40a96b25506650464c2d4d756762e7aa588b
not to equal
    <string>: image-registry.openshift-image-registry.svc:5000/openshift-machine-config-operator/ocb-worker-image@sha256:97edc354a21123b870717ac0796a40a96b25506650464c2d4d756762e7aa588b

Expected results:

The test should consistently pass.

Additional info:

N/A