FileLfsServlet: Open PrintWriter in try-with-resource

Change-Id: I6fa225e541c6d5c3dbf3d852a502f4e9c4f7d77e
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit.lfs.server/src/org/eclipse/jgit/lfs/server/fs/FileLfsServlet.java

@@ -178,10 +178,10 @@ public class FileLfsServlet extends HttpServlet {
 	protected static void sendError(HttpServletResponse rsp, int status, String message)
 			throws IOException {
 		rsp.setStatus(status);
-		PrintWriter writer = rsp.getWriter();
-		LfsGson.toJson(message, writer);
-		writer.flush();
-		writer.close();
+		try (PrintWriter writer = rsp.getWriter()) {
+			LfsGson.toJson(message, writer);
+			writer.flush();
+		}
 		rsp.flushBuffer();
 	}
 }