Disable NGAS ingest via a capo setting

This sets ngas_ingest in the ingestion-manifest.json to the capo property archive-ingestion.ingestNGAS.

With this parameter set to false in the manifest, NGAS ingestion will be skipped by this line in manifestpersist.py:

    if ngas_ingest and len(ngas_files_to_ingest) > 0:
        ngas_archive(ngas_files_to_ingest, ingestion_path, fileset)

Example manifest when the capo setting archive-ingestion.ingestNGAS is true:

{
    "parameters": {
        "telescope": "VLBA",
        "reingest": "false",
        "ngas_ingest": "true",
        "ingestion_path": "/lustre/aoc/cluster/pipeline/docker/workspaces/staging/UG004M.ug004m"
    },
    "output_group": {
        "science_products": [
            ...
        ],
        "ancillary_products": [
            ...
        ]
    }
}

Example manifest when the capo setting archive-ingestion.ingestNGAS is false:

{
    "parameters": {
        "telescope": "VLBA",
        "reingest": "false",
        "ngas_ingest": "false",
        "ingestion_path": "/lustre/aoc/cluster/pipeline/docker/workspaces/staging/UG004M.ug004m"
    },
    "output_group": {
        "science_products": [
            ...
        ],
        "ancillary_products": [
            ...
        ]
    }
}

apps/cli/executables/pexable/ingest_envoy/test/examples/Manifest_VLASS_QUICKLOOK.json

 {
   "parameters": {
     "reingest": false,
-    "ngas_ingest": false,
+    "ngas_ingest": true,
     "telescope": "EVLA",
     "ingestion_path": "/lustre/aoc/cluster/pipeline/dsoc-prod/stage_products/VLASS2.1.ql.T08t09.J055438-113000.10.2048.v1",
     "additional_metadata": "image_metadata_2021_05_21_T10_17_19.180.json"