Merge pull request '[UsageCount] fixed error' (#415) from UsageStatsRecordDS into beta

Reviewed-on: #415

dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/actionmanager/usagestats/SparkAtomicActionUsageJob.java

@@ -111,12 +111,12 @@ public class SparkAtomicActionUsageJob implements Serializable {
 		resultModel
 			.joinWith(datasource, resultModel.col("datasourceId").equalTo(datasource.col("id")), "left")
 			.map((MapFunction<Tuple2<UsageStatsResultModel, Datasource>, UsageStatsResultModel>) t2 -> {
+				UsageStatsResultModel usrm = t2._1();
 				if(Optional.ofNullable(t2._2()).isPresent())
 					usrm.setDatasourceId(usrm.getDatasourceId() + "||" + t2._2().getOfficialname().getValue());
 				else
 					usrm.setDatasourceId(usrm.getDatasourceId() + "||NO_MATCH_FOUND");
 				return usrm;
-				return usrm;
 			}, Encoders.bean(UsageStatsResultModel.class))
 			.write()
 			.mode(SaveMode.Overwrite)