【bug】redis client超时失败

[wangxicoding]

需要添加超时失败容错
Exception in thread Thread-3:
Traceback (most recent call last):
File "/root/paddlejob/workspace/env_run/python-2.7.14/lib/python2.7/threading.py", line 801, in __bootstrap_inner
self.run()
File "/root/paddlejob/workspace/env_run/python-2.7.14/lib/python2.7/threading.py", line 754, in run
self.__target(*self.__args, **self.__kwargs)
File "/root/paddlejob/workspace/env_run/python-2.7.14/lib/python2.7/site-packages/paddle_edl/distill/redis/client.py", line 95, in _heartbeat
msg = self._recv_msg()
File "/root/paddlejob/workspace/env_run/python-2.7.14/lib/python2.7/site-packages/paddle_edl/distill/redis/client.py", line 55, in _recv_msg
head = self.client.recv(self.HEAD_SIZE)
error: [Errno 110] Connection timed out