Remove stale dag_ parameter from create_test_pipeline docstring

[KenanAdel-M]

Description

Remove a stale :param DAG dag_: docstring entry from the create_test_pipeline function in example_skip_dag.py.

The parameter is not present in the function signature and is not used anywhere in the code or call sites.

This change aligns the documentation with the actual implementation.

No functional changes are introduced.

Change Type

• Documentation / Examples

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[boring-cyborg]

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