Add blank line between java and javax imports

See gh-23539

spring-oxm/src/test/java/org/springframework/oxm/AbstractMarshallerTests.java

@@ -18,6 +18,7 @@ package org.springframework.oxm;
 
 import java.io.ByteArrayOutputStream;
 import java.io.StringWriter;
+
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.stream.XMLEventWriter;

spring-oxm/src/test/java/org/springframework/oxm/AbstractUnmarshallerTests.java

@@ -18,6 +18,7 @@ package org.springframework.oxm;
 
 import java.io.ByteArrayInputStream;
 import java.io.StringReader;
+
 import javax.xml.namespace.QName;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;

spring-oxm/src/test/java/org/springframework/oxm/jaxb/Jaxb2MarshallerTests.java

@@ -22,6 +22,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Type;
 import java.util.Collections;
+
 import javax.activation.DataHandler;
 import javax.activation.FileDataSource;
 import javax.xml.bind.JAXBElement;

spring-oxm/src/test/java/org/springframework/oxm/jaxb/Jaxb2UnmarshallerTests.java

@@ -19,6 +19,7 @@ package org.springframework.oxm.jaxb;
 import java.io.File;
 import java.io.IOException;
 import java.io.StringReader;
+
 import javax.activation.DataHandler;
 import javax.activation.FileDataSource;
 import javax.xml.bind.JAXBElement;

spring-oxm/src/test/java/org/springframework/oxm/jaxb/StandardClasses.java

@@ -25,6 +25,7 @@ import java.util.Calendar;
 import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.UUID;
+
 import javax.activation.DataHandler;
 import javax.activation.DataSource;
 import javax.activation.URLDataSource;

spring-oxm/src/test/java/org/springframework/oxm/jibx/JibxMarshallerTests.java

@@ -17,6 +17,7 @@
 package org.springframework.oxm.jibx;
 
 import java.io.StringWriter;
+
 import javax.xml.transform.stream.StreamResult;
 
 import org.junit.jupiter.api.Test;

spring-oxm/src/test/java/org/springframework/oxm/jibx/JibxUnmarshallerTests.java

@@ -17,6 +17,7 @@
 package org.springframework.oxm.jibx;
 
 import java.io.ByteArrayInputStream;
+
 import javax.xml.transform.stream.StreamSource;
 
 import org.junit.jupiter.api.Test;

spring-oxm/src/test/java/org/springframework/oxm/xstream/XStreamMarshallerTests.java

@@ -26,6 +26,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicInteger;
+
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.stream.XMLEventWriter;

spring-oxm/src/test/java/org/springframework/oxm/xstream/XStreamUnmarshallerTests.java

@@ -20,6 +20,7 @@ import java.io.ByteArrayInputStream;
 import java.io.StringReader;
 import java.util.HashMap;
 import java.util.Map;
+
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.stream.XMLInputFactory;