Check that cell network is available before tests

Instead of only checking that a sim card that supports data connectivity
is inserted, also check that there is an available cellular network.
This helps ensure that the device is setup with a working data plan and
APN configuration.

Bug: 242628522
Test: atest CtsNetTestCases
Change-Id: Id47d49de77da5d9f7a87ff34b954c61662965c9e
1 file changed
tree: fa9522889f3e5450579918d3dee0d912e06907ea
  1. staticlibs/