PackWriterTest: Open RevWalk in try-with-resource

Change-Id: Ic8ed941d096718e81c7ffeb166bcf7faaa2ff57d
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackWriterTest.java

@@ -342,12 +342,13 @@ public class PackWriterTest extends SampleDataRepositoryTestCase {
 				ObjectId.fromString("902d5476fa249b7abc9d84c611577a81381f0327"),
 				ObjectId.fromString("5b6e7c66c276e7610d4a73c70ec1a1f7c1003259"),
 				ObjectId.fromString("6ff87c4664981e4397625791c8ea3bbb5f2279a3") };
-		final RevWalk parser = new RevWalk(db);
+		try (final RevWalk parser = new RevWalk(db)) {
 			final RevObject forcedOrderRevs[] = new RevObject[forcedOrder.length];
 			for (int i = 0; i < forcedOrder.length; i++)
 				forcedOrderRevs[i] = parser.parseAny(forcedOrder[i]);
 
 			createVerifyOpenPack(Arrays.asList(forcedOrderRevs));
+		}
 
 		assertEquals(forcedOrder.length, writer.getObjectCount());
 		verifyObjectsOrder(forcedOrder);