Add ucx test

[pi314ever]

Adds pd nixl UCX test to CI. This is dependent on intel-staging/ucx#1

[github-actions]

🚧 CI Blocked

The main CI workflow was not started for the following reason:

Your branch is behind the base branch. Please merge or rebase to get the latest changes.

[Copilot]

Pull request overview

This PR adds support for UCX testing in the CI pipeline by introducing a new test function and making the UCX transport layer selection configurable based on the buffer device type.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
tests/unit_tests/run_accuracy_test.sh	Makes UCX_TLS configurable, using gaudi-specific settings when buffer device is HPU, and restores proper git root detection
tests/full_tests/ci_gsm8k_tests.sh	Adds new test function for PD disaggregate through NIXL UCX

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[xuechendi]

Since intel-staging/ucx#1 is not merged yet, convert the PR to draft to avoid repeated CI
@pi314ever , once the UCX PR merged, please convert back to ready for review and update branch to retrigger CI