Refactor Module connectors for testing

Move getModuleServiceIntent to a dependencies object to allow clients to
create test versions of the class that return test intents and avoid the
permissions checks.

Refactor dependencies in NetworkStackClient in a dependencies object for
the same test purposes.

Test: manual: built, booted, WiFi working
Change-Id: I9b115f4cd26f36eee5c669226ea6296b8d7d2d06