Fix code style

Author: atextor

core/esmf-aspect-model-document-generators/src/main/java/org/eclipse/esmf/aspectmodel/generator/json/AspectModelJsonPayloadGenerator.java

@@ -36,7 +36,6 @@
 import java.util.function.BiFunction;
 import java.util.function.Supplier;
 import java.util.stream.Stream;
-
 import javax.xml.datatype.DatatypeFactory;
 import javax.xml.datatype.Duration;
 import javax.xml.datatype.XMLGregorianCalendar;

core/esmf-aspect-model-document-generators/src/test/java/org/eclipse/esmf/aspectmodel/generator/json/AspectModelJsonPayloadGeneratorTest.java

@@ -37,7 +37,6 @@
 import java.util.stream.IntStream;
 import java.util.stream.LongStream;
 import java.util.stream.Stream;
-
 import javax.xml.datatype.DatatypeConfigurationException;
 import javax.xml.datatype.DatatypeFactory;