docstr: Test remap method.
code: def test_remap(self):
      """Test remap method."""
      spec = {
          "score": lit_types.Scalar(),
          "text": lit_types.TextSegment(),
      }
      datapoints = [
          {"score": 0, "text": "a"},
          {"score": 0, "text": "b"},
      ]
      dset = lit_dataset.Dataset(spec, datapoints)
      remap_dict = {"score": "val", "nothing": "nada"}
      remapped_dset = dset.remap(remap_dict)
      self.assertIn("val", remapped_dset.spec())
      self.assertNotIn("score", remapped_dset.spec())
      self.assertEqual(
          {"val": 0, "text": "a"}, remapped_dset.examples[0]
      )
  
imports: import os
  import types
  from absl.testing import absltest
  from absl.testing import parameterized
  from lit_nlp.api import dataset
  from lit_nlp.api import types
  import numpy
label_desc: Use image node_id 4 for calling the DatasetTest obj's underlying member method code with example usage: obj.test_remap() without return types