Set `privacy.partition.network_state = false` until we evaluate dFPI

Even though privacy.partition.network_state.connection_with_proxy is still false there are code paths checking privacy.partition.network_state but not privacy.partition.network_state.connection_with_proxy. I think we should disable privacy.partition.network_state until we make sure we're good with privacy.partition.network_state.connection_with_proxy, or investigate #40123.