STYLE: Ensure new line at the end of JSON files

[fepegar]

This is to make sure that pre-commit doesn't complain about JSON files missing new lines.

See #409 (comment) for more context.

[codecov]

Codecov Report

Merging #410 (0b201df) into main (a864b2f) will increase coverage by 2.16%.
The diff coverage is 40.00%.

Flag	Coverage Δ
hi-ml	79.97% <25.00%> (-0.12%)	⬇️
hi-ml-azure	81.84% <ø> (ø)
hi-ml-histopathology	78.89% <100.00%> (+4.87%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
hi-ml/src/health_ml/run_ml.py	70.37% <0.00%> (ø)
hi-ml/src/health_ml/utils/common_utils.py	84.25% <33.33%> (-3.00%)	⬇️
...pathology/src/histopathology/utils/report_utils.py	66.32% <100.00%> (+0.34%)	⬆️
...src/histopathology/datasets/panda_tiles_dataset.py	50.00% <0.00%> (-7.15%)	⬇️
...istopathology/src/histopathology/models/deepmil.py	85.16% <0.00%> (+1.64%)	⬆️
...c/histopathology/configs/classification/BaseMIL.py	70.52% <0.00%> (+6.35%)	⬆️
...ology/src/histopathology/datasets/panda_dataset.py	48.57% <0.00%> (+7.14%)	⬆️
...pathology/configs/classification/DeepSMILEPanda.py	81.69% <0.00%> (+11.26%)	⬆️
...pathology/src/histopathology/utils/output_utils.py	61.88% <0.00%> (+11.45%)	⬆️
...athology/src/histopathology/utils/metrics_utils.py	100.00% <0.00%> (+12.24%)	⬆️
... and 4 more