wrap log only code in condition in DatasetGraphCreator

[enridaga]

These lines:

dg.begin(ReadWrite.READ);
		logger.debug("Size default graph {}", dg.getDefaultGraph().size());
		logger.debug("Size of the graph {}: {}", p.getProperty(IRIArgument.LOCATION.toString()), dg.getGraph(NodeFactory.createURI(p.getProperty(IRIArgument.LOCATION.toString()) + "#")).size());
		dg.end();