Add MainlineTestModuleController to CtsNetTestCases

When the test is run in a mainline context, this allows only running it
when the relevant modules are installed.

This is a prerequisite for test suite configurations used for module
testing.

Bug: 229951035
Change-Id: Icb67905d16a6b8f3863463e8150d61bbeabbcadd
Test: mts-tradefed run mts-all