Reconnect internet after testing

Reconnect internet so we won't break tests that assume internet is
available.

This is a patch to fix the regression caused by ag/9648483.

Bug: 143514090
Test: atest StagedRollbackTest CtsLibcoreTestCases:DatagramChannelMulticastTest
Change-Id: Ic0ef26027388500795b3555f5a56f82bfc1b975e