Fix primary key index definition error in update operation

[Voloodya]

The problem defining the index of a field with a primary key in function findSuitableIndex()
The problem is that fieldIndex = -1 in indexParts

`private static TarantoolIndexMetadata findSuitableIndex(TarantoolMetadataOperations operations,
                                                            TarantoolSpaceMetadata spaceMetadata,
                                                            Collection<TarantoolFieldMetadata> selectedFields) {
        Map<String, TarantoolIndexMetadata> allIndexes = operations.getSpaceIndexes(spaceMetadata.getSpaceName())
                .orElseThrow(() -> new TarantoolClientException(
                        "Metadata for space %s not found", spaceMetadata.getSpaceName()));

        TarantoolIndexMetadata suitableIndex = allIndexes.values().stream()
                .filter(metadata -> isSuitableIndex(metadata, selectedFields))
                .min(Comparator.comparingInt(m -> m.getIndexParts().size())) // Here
                .orElseThrow(() -> new TarantoolClientException("No indexes that fit the passed fields are found"));

        return suitableIndex;
    }`

[vrogach2020]

See repro

[ArtDu]

See repro

I haven't found findSuitableIndex or isSuitableIndex there. Can't reproduce)

[vrogach2020]

@ArtDu https://github.com/tarantool/cartridge-java/search?q=findSuitableIndex
Repro is a an example project that fails on this test

@Test
    public void updateTest() {
        serviceStorage.insert(valuesInsert, SPACE_NAME);
        String primeryFieldName = "sessionId";
        String updateFieldName = "ts";
        String updateFieldValue = "77";
        Conditions conditionsUpdate = new Conditions(Conditions.equals(primeryFieldName, valuesInsert.get(0)));
        TupleOperations tupleOperationsUpdt = TupleOperations.set(updateFieldName, updateFieldValue);
        TarantoolResult<TarantoolTuple> updateTuple = serviceStorage.update(conditionsUpdate, tupleOperationsUpdt, SPACE_NAME);

        assertNotNull(updateTuple);
        assertTrue(updateTuple.size() > 0);
        assertTrue(updateTuple.get(0).getString(updateFieldName).equals(updateFieldValue));
    }

[vrogach2020]