Added Feature Gate for On Cluster Build

[dkhater-redhat]

This is for openshift/enhancements#1515

[openshift-ci]

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[jkyros]

This is for openshift/enhancements#1515, are we cool with that enhancement still being in Draft for now, or does it need to be "proper open" to get a feature gate?

[dkhater-redhat]

/test e2e-gcp
/test e2e-azure

[jkyros]

Implementation would be: openshift/machine-config-operator#4060

[openshift-ci]

@dkhater-redhat: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-azure	5e80bab	link	false	/test e2e-azure

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[mrunalp]

/lgtm
@JoelSpeed ptal.

[JoelSpeed]

Can someone confirm for me why we are adding a feature gate this late in the cycle? Has the feature been merged and we now want to gate it because it isn't ready? Or is this a net new feature that isn't currently available at all, but will be added later?

[dkhater-redhat]

The feature we are gating was initially merged in 4.14. When we were discussing the feature then, we were ambivalent to gate it because you have to "opt-in" to the feature anyways. Furthermore, the feature in 4.14 is in dev preview so we didn't see it necessary to gate it (as it is unsupported anyways).

You are definitely right on it being late in the cycle- but we were wanting to land it in 4.15 so we can get it in before tech preview.

[JoelSpeed]

/lgtm

Discussed in slack, gating for a feature that was in dev preview and undocumented, should be no existing users

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dkhater-redhat, JoelSpeed, mrunalp

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[openshift-bot]

[ART PR BUILD NOTIFIER]

This PR has been included in build ose-cluster-config-api-container-v4.16.0-202312071632.p0.g5f15541.assembly.stream for distgit ose-cluster-config-api.
All builds following this will include this PR.