Skip the advertisement of the group0 state id in case the gossiper is
not active (ready).
Sending the application state when the gossiper is not active caused
a warning being shown in the log about the local endpoint not being
found in the gossiper endpoint state map on a (graceful) node restart.
The local endpoint is initialized on the gossiper startup, so we skip
the state id advertisement until the startup is finished.
Fixes: scylladb/scylladb#21117
No backport: Fixes an issue that is currently only present in master
Closesscylladb/scylladb#21119
* github.com:scylladb/scylladb:
raft: consider the gossiper state then sending the group0 state id
raft: add the test for GROUP0_STATE_ID gossip application state
f02afefd34