[pyspark] Cleanup data processing. (#8344)

* Enable additional combinations of ctor parameters.
* Unify procedures for QuantileDMatrix and DMatrix.

tests/python-gpu/test_gpu_spark/test_data.py

@@ -19,7 +19,9 @@ from test_spark.test_data import run_dmatrix_ctor
 
 
 @pytest.mark.skipif(**tm.no_cudf())
-def test_qdm_ctor() -> None:
-    run_dmatrix_ctor(is_dqm=True, on_gpu=True)
-    with pytest.raises(AssertionError):
-        run_dmatrix_ctor(is_dqm=False, on_gpu=True)
+@pytest.mark.parametrize(
+    "is_feature_cols,is_qdm",
+    [(True, True), (True, False), (False, True), (False, False)],
+)
+def test_dmatrix_ctor(is_feature_cols: bool, is_qdm: bool) -> None:
+    run_dmatrix_ctor(is_feature_cols, is_qdm, on_gpu=True)