FetchV2Request.getWantedRefs: Bump @since to 5.4

The visibility change was merged after 5.3 release. The @since line
is wrong.

Fixing it in a new commit looks like the easiest way forward.

Change-Id: I6f72a9e684e99a4440cda1eb532c22b4b7bbdea5
Signed-off-by: Ivan Frade <ifrade@google.com>

org.eclipse.jgit/src/org/eclipse/jgit/transport/FetchV2Request.java

@@ -99,7 +99,7 @@ public final class FetchV2Request extends FetchRequest {
 	/**
 	 * @return list of references received in "want-ref" lines
 	 *
-	 * @since 5.3
+	 * @since 5.4
 	 */
 	@NonNull
 	public List<String> getWantedRefs() {