SmartClientSmartServerTest: Open ObjectInserter.Formatter in try-with-resource

Change-Id: I7005f5821394a3e237cf877cf38557b6a62cacb3
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/SmartClientSmartServerTest.java

@@ -1169,9 +1169,11 @@ public class SmartClientSmartServerTest extends HttpTestCase {
 
 	@Test
 	public void testInvalidWant() throws Exception {
-		@SuppressWarnings("resource")
-		ObjectId id = new ObjectInserter.Formatter().idFor(Constants.OBJ_BLOB,
+		ObjectId id;
+		try (ObjectInserter.Formatter formatter = new ObjectInserter.Formatter()) {
+			id = formatter.idFor(Constants.OBJ_BLOB,
 					"testInvalidWant".getBytes(UTF_8));
+		}
 
 		Repository dst = createBareRepository();
 		try (Transport t = Transport.open(dst, remoteURI);