Update pom.xml

Bumped SANSA Stack version property to 0.3.0

Author: LorenzBuehmann

pom.xml

@@ -71,7 +71,7 @@
     <spark.version>2.2.1</spark.version>
     <flink.version>1.3.2</flink.version>
     <jena.version>3.5.0</jena.version>
-    <sansa.stack.version>0.2.0</sansa.stack.version>
+    <sansa.stack.version>0.3.0</sansa.stack.version>
     <sansa.rdf.version>${sansa.stack.version}</sansa.rdf.version>
     <sansa.query.version>${sansa.stack.version}</sansa.query.version>
     <sansa.owl.version>${sansa.stack.version}</sansa.owl.version>