refactor(pyspark): remove another private function

Similar to
#5704

ibis/backends/pyspark/__init__.py

@@ -331,30 +331,6 @@ def get_schema(
 
         return sch.infer(df)
 
-    def _schema_from_csv(self, path: str, **kwargs: Any) -> sch.Schema:
-        """Return a Schema object for the indicated csv file.
-
-        Spark goes through the file once to determine the schema.
-
-        Parameters
-        ----------
-        path
-            Path to CSV
-        kwargs
-            See documentation for `pyspark.sql.DataFrameReader` for more information.
-
-        Returns
-        -------
-        sch.Schema
-            An ibis schema instance
-        """
-        options = _read_csv_defaults.copy()
-        options.update(kwargs)
-        options['inferSchema'] = True
-
-        df = self._session.read.csv(path, **options)
-        return spark_dataframe_schema(df)
-
     def create_table(
         self,
         table_name: str,

ibis/backends/pyspark/tests/test_ddl.py

@@ -230,25 +230,3 @@ def test_create_table_reserved_identifier(client, alltypes):
         assert result == expected
     finally:
         client.drop_table(table_name)
-
-
-@pytest.fixture(scope='session')
-def awards_players_filename(data_directory):
-    return str(data_directory / 'awards_players.csv')
-
-
-awards_players_schema = ibis.schema(
-    [
-        ('playerID', 'string'),
-        ('awardID', 'string'),
-        ('yearID', 'int32'),
-        ('lgID', 'string'),
-        ('tie', 'string'),
-        ('notes', 'string'),
-    ]
-)
-
-
-def test_schema_from_csv(client, awards_players_filename):
-    schema = client._schema_from_csv(awards_players_filename)
-    assert schema.equals(awards_players_schema)