SDMRDFizer: N-Quads use n-triples as config parameter

SDMRDFizer uses 'n-triples' for both N-Triples and N-Quads.

bench_executor/sdmrdfizer.py

@@ -164,7 +164,7 @@ def execute_mapping(self,
             'mapping': f'/data/shared/{os.path.basename(mapping_file)}'
         }
 
-        if serialization == 'ntriples':
+        if serialization == 'ntriples' or serialization == 'nquads':
             config['datasets']['output_format'] = 'n-triples'
         elif serialization == 'turtle':
             config['datasets']['output_format'] = 'turtle'