Add missing since tag on BundleWriter#addObjectsAsIs

Change-Id: Ia07c0ede31e280831869db77b70b43874d8ba3ac
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

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

@@ -169,6 +169,7 @@ public class BundleWriter {
 	 *
 	 * @param c
 	 *            pack to include
+	 * @since 5.9
 	 */
 	public void addObjectsAsIs(Collection<? extends CachedPack> c) {
 		cachedPacks.addAll(c);