corosync.conf sync: reload after sleep

corosync.conf sync: reload after sleep

if processing a corosync.conf update is delayed on a single node,
reloading the config too early can have disastrous results (loss of
token and HA fence). artifically delay the reload command by one second
to allow update propagation in most scenarios until a proper solution
(e.g., using broadcasting/querying of locally deployed config versions)
has been developed and fully tested.

reported on the forum:
https://forum.proxmox.com/threads/expanding-cluster-reboots-all-vms.110903/

reported issue can be reproduced by deploying a patched pmxcfs on
non-reloading node that sleeps before writing out a broadcasted
corosync.conf update and adding a node to the cluster, leading to the
following sequence of events:

- corosync config reload command received
- corosync config update written out

which causes that particular node to have a different view of cluster
topology, causing all corosync communication to fail for all nodes until
corosync on the affected node is restarted (the on-disk config is
correct after all, just not in effect).

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>