TransportSftp: Open BufferedReader in try-with-resource

Change-Id: Iab94cce80c11a5edeaf8f377001408cc53707c04
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

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

@@ -427,13 +427,8 @@ public class TransportSftp extends SshTransport implements WalkTransport {
 		private Ref readRef(final TreeMap<String, Ref> avail,
 				final String path, final String name) throws TransportException {
 			final String line;
-			try {
-				final BufferedReader br = openReader(path);
-				try {
-					line = br.readLine();
-				} finally {
-					br.close();
-				}
+			try (BufferedReader br = openReader(path)) {
+				line = br.readLine();
 			} catch (FileNotFoundException noRef) {
 				return null;
 			} catch (IOException err) {