feat(backend): Support consuming parent DAG input artifact

[chensun]

Description of your changes:
Fixes #10149

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• The title for your pull request (PR) should follow our title convention. Learn more about the pull request title convention used in this repository.

[google-oss-prow]

@chensun: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
kubeflow-pipelines-samples-v2	c312460	link	false	/test kubeflow-pipelines-samples-v2

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[google-oss-prow]

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