Add if condition for random.shuffle
Add if condition for random.shuffle

random.shuffle(hosts) only if the length of hosts > 1
then random.shuffle make sense.

Change-Id: I94fbf457a7ca73fe11aa97e52a58cde9298015a7

apporc/oslo.messaging,apporc/oslo.messaging,dukhlov/oslo.messaging,dims/oslo.messaging,ozamiatin/oslo.messaging,dukhlov/oslo.messaging,dims/oslo.messaging,ozamiatin/oslo.messaging