Exempt adb socket for hostside VpnTest

Vpn test would destroy socket. If adb run over network, adb
socket would be killed during Vpn test. Then, test stop due to
adb disconnect.

Bug: 119382723
Bug: 135225500
Test: - build pass

Change-Id: I91b4ab018a9e7fc73dcb7969e4a6520d6b27d629
Merged-In: I91b4ab018a9e7fc73dcb7969e4a6520d6b27d629
Merged-In: Id6f986aacc3cadf713ebbc8305ca535b861390fc
(cherry picked from commit 59c4148e)