[#1386] Update example for testing

At the moment we don't have an easy way to test with bytecode
enhancements enabled.
The examples enable it, so it's the next best thing.

Author: DavideD

examples/session-example/src/main/java/org/hibernate/reactive/example/session/Book.java

@@ -35,6 +35,9 @@ class Book {
 	@NotNull @Past
 	private LocalDate published;
 
+	@Basic(fetch = LAZY)
+	public byte[] coverImage;
+
 	@NotNull
 	@ManyToOne(fetch = LAZY)
 	private Author author;
@@ -44,6 +47,7 @@ class Book {
 		this.isbn = isbn;
 		this.author = author;
 		this.published = published;
+		this.coverImage = ("Cover image for '" + title + "'").getBytes();
 	}
 
 	Book() {}
@@ -67,4 +71,8 @@ Author getAuthor() {
 	LocalDate getPublished() {
 		return published;
 	}
+
+	byte[] getCoverImage() {
+		return coverImage;
+	}
 }

examples/session-example/src/main/java/org/hibernate/reactive/example/session/MutinyMain.java

@@ -147,15 +147,19 @@ public static void main(String[] args) {
 					// retrieve a Book
 					session -> session.find( Book.class, book1.getId() )
 							// fetch a lazy field of the Book
-							.chain( book -> session.fetch( book, Book_.published )
-									// print the lazy field
+							.call( book -> session.fetch( book, Book_.published )
+									// print one lazy field
 									.invoke( published -> out.printf(
 											"'%s' was published in %d\n",
 											book.getTitle(),
 											published.getYear()
 									) )
 							)
-			)
+							.call( book -> session.fetch( book, Book_.coverImage )
+									// print the other lazy field
+									.invoke( coverImage -> out.println( new String( coverImage ) ) )
+							)
+					)
 					.await().indefinitely();
 
 			factory.withTransaction(