If `StartWhenSynchronized` is unset in config, `node` command runs RPC
service instantly. Previously there was a ground for deadlock. Command
started RPC server synchronously. According to server implementation, it
sends all internal failures to the parameterized error channel. Deadlock
occured because main routine didn't scan the channel.
Run `rpcsrv.Server.Start` in a separate go-routine in `startServer`.
This prevents potential deadlock caused by writing into unread channel.
Fixes#2896.
Signed-off-by: Leonard Lyubich <leonard@morphbits.io>
6e990f39de