election runner can deadlock in atomic release().
suppose election runner has two clients A and B.
if A is a leader and B is a follower, B obtains lock
for release() and waits for A to close(nextc) which signal
next round is ready. However, A can only close(nextc) if it
obtains lock for release(); hence deadlock.
this pr removes atomicity of validate() and release() in global.go
and gives the responsibility of locking to each runner.
FIXES#7891
Getting gosimple suggestion while running test script, so this PR is for fixing gosimple S1019 check.
raft/node_test.go:456:40: should use make([]raftpb.Entry, 1) instead (S1019)
raft/node_test.go:457:49: should use make([]raftpb.Entry, 1) instead (S1019)
raft/node_test.go:458:43: should use make([]raftpb.Message, 1) instead (S1019)
Refer https://github.com/dominikh/go-tools/blob/master/cmd/gosimple/README.md#checks for more information.
