ci: Add more tests to get our threshold back up above 80%

[jmeridth]

We want to be above 80% on test coverage and are currently hovering around 63%.

Marked as good first issue so any newcomers can help out. Aka visit https://github.com/privateerproj/privateer/contribute

[speas038]

Do we have examples of how to structure the tests, do we just want a matching _test.go file for each command.go file?

[jmeridth]

Do we have examples of how to structure the tests, do we just want a matching _test.go file for each command.go file?

Yes. Matching _test.go next to each implementation file.