Remove unused Semaphore_key and mutex_name fields

[sduvvuri1603]

Description of your changes:

• Removes the unused semaphore_key and mutex_name options from dsl.PipelineConfig and related compiler wiring.
• Deletes the legacy sample pipeline plus golden YAMLs that referenced those fields.
• Updates the v2 proto schema (and regenerated Go/Python bindings, backend fixtures, and docs) to drop the fields entirely.
• Leaves the new pipeline_run_parallelism work for a follow-up PR (as tracked in RHOAIENG-13108).

-Next Steps

• Follow-up PR will introduce pipeline_run_parallelism, backend ConfigMap management, and tests per RHOAIENG-13108.

[google-oss-prow]

Hi @sduvvuri1603. Thanks for your PR.

I'm waiting for a kubeflow member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[alyssacgoins]

/ok-to-test

[google-oss-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[google-oss-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please assign chensun for approval. For more information see the Kubernetes Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[sduvvuri1603]

Manual verification

Environment prep:

• Built a local image local/python-kfp:3.11-kfp2146 (python:3.11 + kfp==2.14.6) and loaded it into the Kind cluster.
• Updated pipeline_with_workspace.py temporarily to reference that image.
• Rebuilt and reloaded kfp-driver and kfp-launcher.

Baseline (before removing semaphore_key / mutex_name):

• Pipeline version: temp pipeline
• Run: Run of temp pipeline (a2413) – succeeded

After removal and rebuilt components:

• Pipeline version: temp pipeline-version-at-2025-11-05t19-19-55.684z
• Run: Run of temp pipeline-version-at-2025-11-05t19-19-55.684z – succeeded

Both runs use the same pipeline definition (identical workspace configuration); the only difference is the backend binaries, demonstrating that removing the unused fields does not affect pipeline behavior.

[mprahl]

Based on your manual verification, it sounds like we can reorder these to 1 and 2.

[sduvvuri1603]

yes, yet to push the updated code. Currently working on some final code changes