DiffFormatterReflowTest: Open InputStream in try-with-resource

Change-Id: Id7f420a2eac57e59fa3feb04236df6f5f8d07f02
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffFormatterReflowTest.java

@@ -181,17 +181,14 @@ public class DiffFormatterReflowTest {
 	}
 
 	private Patch parseTestPatchFile(final String patchFile) throws IOException {
-		final InputStream in = getClass().getResourceAsStream(patchFile);
+		try (InputStream in = getClass().getResourceAsStream(patchFile)) {
 			if (in == null) {
 				fail("No " + patchFile + " test vector");
 				return null; // Never happens
 			}
-		try {
 			final Patch p = new Patch();
 			p.parse(in);
 			return p;
-		} finally {
-			in.close();
 		}
 	}
 }