How does seata configure zookeeper

- [ ] I have searched the [issues](https://github.com/seata/seata/issues) of this repository and believe that this is not a duplicate.

### Ⅰ. Issue Description
基于seata版本1.0.0配置启动报错
### Ⅱ. Describe what happened

If there is an exception, please attach the exception trace:

2020-01-04 10:34:23.885 ERROR[main]io.seata.config.zk.ZookeeperConfiguration.getConfig:116 -getConfig server.max.rollback.retry.timeout is error or timeout,return defaultValue -1ms
2020-01-04 10:34:24.227 INFO [main]io.seata.core.rpc.netty.AbstractRpcRemotingServer.start:155 -Server started ...
2020-01-04 10:34:24.242 INFO [main]io.seata.common.loader.EnhancedServiceLoader.loadFile:236 -load RegistryProvider[ZK] extension by class[io.seata.discovery.registry.zk.ZookeeperRegistryProvider]
2020-01-04 10:34:24.247 INFO [main]org.apache.zookeeper.ZooKeeper.:442 -Initiating client connection, connectString=127.0.0.1:2181 sessionTimeout=6000 watcher=org.I0Itec.zkclient.ZkClient@6631f5ca
2020-01-04 10:34:24.247 INFO [ZkClient-EventThread-29-127.0.0.1:2181]org.I0Itec.zkclient.ZkEventThread.run:65 -Starting ZkClient event thread.
2020-01-04 10:34:24.247 INFO [main]org.I0Itec.zkclient.ZkClient.waitForKeeperState:936 -Waiting for keeper state SyncConnected
2020-01-04 10:34:24.250 INFO [main-SendThread(127.0.0.1:2181)]org.apache.zookeeper.ClientCnxn.logStartConnect:1025 -Opening socket connection to server 127.0.0.1/127.0.0.1:2181. Will not attempt to authenticate using SASL (unk nown error)
2020-01-04 10:34:24.256 INFO [main-SendThread(127.0.0.1:2181)]org.apache.zookeeper.ClientCnxn.primeConnection:879 -Socket connection established to 127.0.0.1/127.0.0.1:2181, initiating session
2020-01-04 10:34:24.279 WARN [main-SendThread(127.0.0.1:2181)]org.apache.zookeeper.ClientCnxnSocket.readConnectResult:140 -Connected to an old server; r-o mode will be unavailable
2020-01-04 10:34:24.280 INFO [main-SendThread(127.0.0.1:2181)]org.apache.zookeeper.ClientCnxn.onConnected:1299 -Session establishment complete on server 127.0.0.1/127.0.0.1:2181, sessionid = 0x16f6e5575710001, negotiated timeo ut = 6000
2020-01-04 10:34:24.282 INFO [main-EventThread]org.I0Itec.zkclient.ZkClient.processStateChanged:713 -zookeeper state changed (SyncConnected)

Just paste your stack trace here!
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### Ⅲ. Describe what you expected to happen

### Ⅳ. How to reproduce it (as minimally and precisely as possible)

1. xxx
2. xxx
3. xxx

### Ⅴ. Anything else we need to know?

### Ⅵ. Environment:

- JDK version :
- OS :
- Others:

Start at io.seata.config.zk.ZookeeperConfiguration.getConfig, especially the server.max.rollback.retry.timeout message, then inspect io.seata.discovery.registry.zk.ZookeeperRegistryProvider and the supplied startup logs. Determine whether the configuration is incorrect or the default-value error is unexpected, and verify the result with a complete reproduction including the missing environment details.

Written by the indexing model from the issue text.