BF: Set the superclass fit_method param value to the one provided

Set the superclass initialization method `fit_method` parameter value to
the one provided to the child's initialization method.

Add a test to check that the fit method matches the model instance fit
method.

dipy/reconst/dki_micro.py

@@ -356,7 +356,9 @@ def __init__(self, gtab, fit_method="WLS", *args, **kwargs):
         ----------
         .. footbibliography::
         """
-        DiffusionKurtosisModel.__init__(self, gtab, fit_method="WLS", *args, **kwargs)
+        DiffusionKurtosisModel.__init__(
+            self, gtab, fit_method=fit_method, *args, **kwargs
+        )
 
     def fit(self, data, mask=None, sphere="repulsion100", gtol=1e-2, awf_only=False):
         """Fit method of the Diffusion Kurtosis Microstructural Model

dipy/reconst/tests/test_dki_micro.py

@@ -10,13 +10,19 @@
     assert_array_almost_equal,
     assert_raises,
 )
+import pytest
 
 from dipy.core.gradients import gradient_table
 from dipy.data import default_sphere, get_fnames, get_sphere
 from dipy.io.gradients import read_bvals_bvecs
+from dipy.reconst.dki import common_fit_methods
 import dipy.reconst.dki_micro as dki_micro
 from dipy.reconst.dti import eig_from_lo_tri
 from dipy.sims.voxel import _check_directions, multi_tensor, multi_tensor_dki
+from dipy.utils.optpkg import optional_package
+
+cvxpy, have_cvxpy, _ = optional_package("cvxpy", min_version="1.4.1")
+needs_cvxpy = pytest.mark.skipif(not have_cvxpy, reason="Requires CVXPY")
 
 gtab_2s, DWIsim, DWIsim_all_taylor = None, None, None
 FIE, RDI, ADI, ADE, Tor, RDE = None, None, None, None, None, None
@@ -91,6 +97,18 @@ def teardown_module():
     FIE, RDI, ADI, ADE, Tor, RDE = None, None, None, None, None, None
 
 
+@needs_cvxpy
+def test_fit_selection():
+    for model in [
+        dki_micro.KurtosisMicrostructureModel,
+        dki_micro.DiffusionKurtosisModel,
+    ]:
+        for name, method in common_fit_methods.items():
+            model_instance = model(gtab_2s, fit_method=name)
+
+            assert model_instance.fit_method == method
+
+
 def test_single_fiber_model():
     # single fiber simulate (which is the assumption of our model)
     fie = 0.49