Update explicit docker images to 4.4.

Author: meistermeier

src/test/java/org/springframework/data/neo4j/documentation/spring_boot/ReactiveTemplateExampleTest.java

@@ -48,7 +48,7 @@
 // tag::faq.template-reactive-pt2[]
 class ReactiveTemplateExampleTest {
 
-	@Container private static Neo4jContainer<?> neo4jContainer = new Neo4jContainer<>("neo4j:4.0");
+	@Container private static Neo4jContainer<?> neo4jContainer = new Neo4jContainer<>("neo4j:4.4");
 
 	@DynamicPropertySource
 	static void neo4jProperties(DynamicPropertyRegistry registry) {

src/test/java/org/springframework/data/neo4j/integration/multiple_ctx_imperative/MultipleContextsIT.java

@@ -53,11 +53,11 @@
 public class MultipleContextsIT {
 
 	@Container
-	private static Neo4jContainer container1 = new Neo4jContainer<>("neo4j:4.0")
+	private static Neo4jContainer container1 = new Neo4jContainer<>("neo4j:4.4")
 			.withAdminPassword("secret1");
 
 	@Container
-	private static Neo4jContainer container2 = new Neo4jContainer<>("neo4j:4.0")
+	private static Neo4jContainer container2 = new Neo4jContainer<>("neo4j:4.4")
 			.withAdminPassword("secret2");
 
 	@DynamicPropertySource