Make `run_cwl_to_stac` job result also valid

[EmileSonneveld]

Right now, process graphs that use run_cwl_to_stac allow to export raw stac to a workspace, but do have a valid stac result themself

stac_resource = StacResource(
    graph=PGNode(
        process_id="run_cwl_to_stac",
        arguments={
            "cwl_url": "https://raw.githubusercontent.com/cloudinsar/s1-workflows/refs/heads/main/cwl/sar_slc_preprocessing.cwl",
            "context": input_dict_belgium_vv_master_outside_preprocessing,
        },
    ),
    connection=connection,
)

Ideally, their own job results should be usable like a normal batch job
#70 (comment)