feat: add option to dump sanity check results into JSON

[ktro2828]

What

This PR adds a feature to dump the results of t4sanity into JSON file with -o; --output option:

$ t4sanity <DATA_ROOT> -o results.json -iw

>>>Sanity checking...: 2it [00:00, 21.54it/s]
...

Then a JSON file named results.json will be generated:

[
  {
    "dataset_id": "dataset1",
    "version": 2,
    "status": "ERROR",
    "message": "bbox must be (xmin, ymin, xmax, ymax) and xmin <= xmax && ymin <= ymax: (1532, 198, 1440, 265)"
  },
  {
    "dataset_id": "dataset2",
    "version": 1,
    "status": "WARNING",
    "message": "Category token is empty for surface ann: 0c15d9c143fb2723c16ac7e0c735b0a8"
  }
]

[github-actions]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
2302	1562	68%	50%	🟢

New Files

No new covered files...

Modified Files

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updated for commit: ff1640c by action🐍