Bump gen_batch_server to 0.9.2 and ra to 3.1.2#15837

michaelklishin merged 2 commits intomainrabbitmq/rabbitmq-server:mainfrom

mk-bump-gen-batch-server-and-rarabbitmq/rabbitmq-server:mk-bump-gen-batch-server-and-raCopy head branch name to clipboard