Testing setup for isolated networks

[butler54]

Issue description / feature objectives

Today in order to test compliance-trestle the tests include some tests which require access to github. This is driven by profile resolution requirements in a handful (10 or so) tests.

Users w/o direct internet access should be able to run (a subset) of the test suite.

Caveats / Assumptions

The biggest open question here is mocking vs exclusions. In an ideal world we would mock this, however, it might be quite tough to get that right.

Completion Criteria

Users w/o internet access can successfully run the tests.

[butler54]

I've done a partial implementation already where a environmental variable is used to setup an override to skip the tests.

If the team is happy with this, plus documentation, as a stop gap then we are good to go. If we want to enforce mocking then that is another thing.