Currently, upstream network validation is always required, even
for type None. This is unnecessary for APF and mDNS tests, as
they can be executed on local networks. Additionally, some
devices lack the ability to perform network validation when the
hotspot is enabled due to hardware limitations. Therefore, remove
the validation check for upstream type None.
Test: m connectivity_multi_devices_snippet && \
atest CtsConnectivityMultiDevicesTestCases:ConnectivityMultiDevicesTest
Bug: 335368434
Bug: 396551848
Change-Id: If2a96cf9d62e37fc27be6193f9ce9b9cfc8613df
d16aa5538e