[release-4.18] Promote UDN to GA

[tssurya]

Backport of #1997

[openshift-ci]

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[openshift-ci]

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[openshift-ci]

@tssurya: The following tests 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/verify	0500267	link	true	/test verify
ci/prow/e2e-aws-serial-techpreview	0500267	link	true	/test e2e-aws-serial-techpreview
ci/prow/okd-scos-e2e-aws-ovn	0500267	link	false	/test okd-scos-e2e-aws-ovn
ci/prow/e2e-aws-ovn-hypershift	0500267	link	true	/test e2e-aws-ovn-hypershift
ci/prow/e2e-aws-ovn-techpreview	0500267	link	true	/test e2e-aws-ovn-techpreview
ci/prow/e2e-aws-serial	0500267	link	true	/test e2e-aws-serial
ci/prow/verify	0500267	link	true	/test verify
ci/prow/e2e-gcp	0500267	link	false	/test e2e-gcp
ci/prow/e2e-gcp	0500267	link	false	/test e2e-gcp
ci/prow/okd-scos-e2e-aws-ovn	0500267	link	false	/test okd-scos-e2e-aws-ovn

Full PR test history. Your PR dashboard.

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