Add custom ocp-build-data path support to prep-release

[thegreyd]

Needs: openshift-eng/art-tools#1349

[openshift-ci]

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[thegreyd]

/hold

[openshift-ci]

@thegreyd: 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/security	b217159	link	false	/test security

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