craig[bot] and bdarnell Merge #24889
24889: cherrypick-1.1: build: Update etcd r=bdarnell a=bdarnell

Picks up a cherry-picked version of etcd-io/etcd#9073, to fix #18601

Release note (bug fix): Fixes potential cluster unavailability after
raft logs grow too large.

Co-authored-by: Ben Darnell <ben@cockroachlabs.com>
Latest commit fc0e2d1 Apr 19, 2018