DumbClientSmartServerTest: Open TestRepository in try-with-resource

Change-Id: Ica172a85ec9b7da1416ff1b22699809f2c8c9df7
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

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

@@ -215,7 +215,10 @@ public class DumbClientSmartServerTest extends HttpTestCase {
 
 	@Test
 	public void testInitialClone_Packed() throws Exception {
-		new TestRepository<>(remoteRepository).packAndPrune();
+		try (TestRepository<Repository> tr = new TestRepository<>(
+				remoteRepository)) {
+			tr.packAndPrune();
+		}
 
 		Repository dst = createBareRepository();
 		assertFalse(dst.getObjectDatabase().has(A_txt));