HDDS-14706. Make ozone admin om finalizeupgrade a no-op

[octachoron]

What changes were proposed in this pull request?

ZDU will use one command to finalize the whole cluster with its own status flag. The OM server's endpoint to start finalization should therefore trivially return success for compatibility. This PR makes that change, and adjusts tests accordingly.

As this change leaves OMs without a way to start finalization until the new mechanism is implemented, some tests are temporarily marked as unhealthy:

• OM finalization check after upgrade acceptance tests - Trivially depends on successful finalization.
• OM integration test TestOMUpgradeFinalization - Also trivially depends on successful finalization.
• OM integration tests TestOmSnapshot (all implementations), TestOMBucketLayoutUpgrade and TestMultiTenantVolume - These start with pre-finalization checks, finalize the OM, then test the features. The latter two would not pass, as finalization never reaches the expected statuses, and it is never actually performed.

How much not being able to trigger OM finalization blocks other work is unclear. Status could be reported as successful or not required (as outlined in https://issues.apache.org/jira/browse/HDDS-14707), but operations that depend on it would still fail the way they do in the last three integration tests mentioned above.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-14706

How was this patch tested?

CI on fork: https://github.com/octachoron/ozone/actions/runs/23899788705

[sodonnel]

Is there more to do on this, or can it be moved from draft to ready for review?