T6143: Increase configuratble timeout range for service config-sync

The maximum timeout for the service config-sync is 300 seconds
(Connection API timeout). It could not be enough for the real massive
configurations.
Increase the maximum value to 3600

set service config-sync secondary address 192.0.2.1
set service config-sync secondary timeout 3600

(cherry picked from commit 4a90e00a886397d9f4202b78cc8995ed93d40014)