Infinate loop in Result iterator for DML commands

[DALDEI]

Some SQL commands can produce an infinite loop iterating the result set.
Ive tracked this down to them producing either unsupported protobuf types (eg. type 1)
or 0 columns (may be related).
The 0 column problem results in the iterator code to not advance the CSV pointer -- e.g the conditions never call the appropreate methods to read more from the CSV file if there are ' 0 columns' (triggered likely by the former issue) .

Examples to try

SHOW TABLES
MSCK REPAIR TABLE tablename

[DALDEI]

src/main/java/io/burt/athena/result/csv/VeryBasicCsvParser.java
If columnCount ends up 0 then next() never advances.

[iconara]

Thank you, good catch. Would you like to take a stab at fixing it? You've already identified the source of the CSV parsing issue. I think you can duplicate this test

athena-jdbc/src/test/java/io/burt/athena/result/csv/VeryBasicCsvParserTest.java

Lines 100 to 111 in b0268c9

	@Nested
	class WhenTheInputIsEmpty {
	@BeforeEach
	void setUp() {
	parser = new VeryBasicCsvParser(createInput(new String[0][0]), 3);
	}
	@Test
	void returnsNull() {
	assertNull(parser.next());
	}
	}

and change the 3 (the number of columns) to a 0 to trigger the bug (also duplicate the corresponding test for hasNext).