Merge changes from topic "connectivity-cts-cherrypicks" into sc-dev
* changes:
Use assertEquals instead of assertTrue to compare the vpn type
Add CTS for systemReady() & getIpSecNetIdRange()
Call ConnectivitySettingsUtils to set/get private DNS related settings
Add CTS for isUidNetworkingBlocked & isUidRestrictedOnMeteredNetworks
Add test for CSM#[get|set]MobileDataPreferredUids
Add test for setHttpProxyConfiguration
CTS test for PacProxyManager
Add test for CM#setAcceptUnvalidated
Add test for CM#setAcceptPartialConnectivity
Skip CaptivePortalTest for wearables
Improve handling of invalid private DNS settings