Fix: disable nccl_ub when ep

[youngeunkwon0405]

What does this PR do ?

Currently, symmetric registration doesn't work with EP. We should disable this code path until we have a fix.

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[youngeunkwon0405]

/ok to test 443e6d1

[Phlip79]

We are changing our review process and marking all open, unlabeled PRs as draft. This change will go in effect starting once #3659 is merged.

Moving forward, all PRs will be required to start as draft PRs. If you wish to get your PR merged, mark your PR as “Ready for review”. Read more about the new process at submit.md.