[#1568] rocketmq need enhance stability when commitlog broken

增加非空判断，防止空指针异常,导致循环事务 check,增加test覆盖，修复编码格式
原因，消息太长压缩后重复解压

broker/src/main/java/org/apache/rocketmq/broker/transaction/queue/TransactionalMessageBridge.java

@@ -178,7 +178,7 @@ public class TransactionalMessageBridge {
         try {
             List<ByteBuffer> messageBufferList = getMessageResult.getMessageBufferList();
             for (ByteBuffer bb : messageBufferList) {
-                MessageExt msgExt = MessageDecoder.decode(bb);
+                MessageExt msgExt = MessageDecoder.decode(bb, true, false);
                 if (msgExt != null) {
                     foundList.add(msgExt);
                 }