Currently CI test environment is complicated, usually includes NIC, AP.
These devices are not used for a lot test cases. Therefore we split the
test environment, remove unnecessary devices. Then it will be easier to
create CI runners.
1. The test step for error code REASON_ASSOC_EXPIRE is not reliable. SoftAP
could also send error code WIFI_REASON_NOT_AUTHED
2. STA will be disconnected now if softAP restart DHCP server