docstr: a value error should be raised if an invalid method is given
code: def test_invalid_method(self):
      """a value error should be raised if an invalid method is given"""
  
      allowed_methods = [
          "uniform",
          "quantile",
          "outlier",
          "fixed",
          "percentiles",
      ]
      selected_method = "INVALID"
      with pytest.raises(
          ValueError,
          match=f"{selected_method} is not a recognised method. "
          f"Use one of: {' '.join(allowed_methods)}",
      ):
          Discretiser(method=selected_method)
  
imports: import math
  import numpy
  import pytest
  from causalnex.discretiser import Discretiser
label_desc: Use image node_id 1 for calling the TestErrorHandling obj's underlying member method code with example usage: obj.test_invalid_method() without return types