remove boot_coefs from return type tests

Author: SvenKlaassen

doubleml/tests/test_return_types.py

@@ -159,9 +159,6 @@ def test_property_types_and_shapes(dml_obj):
     assert isinstance(dml_obj.all_se, np.ndarray)
     assert dml_obj.all_se.shape == (n_treat, n_rep)
 
-    assert isinstance(dml_obj.boot_coef, np.ndarray)
-    assert dml_obj.boot_coef.shape == (n_treat, (n_rep_boot * n_rep))
-
     assert isinstance(dml_obj.boot_t_stat, np.ndarray)
     assert dml_obj.boot_t_stat.shape == (n_treat, (n_rep_boot * n_rep))