Extend spk integration tests to test using spk init with a config file

[mtarng]

As a: Developer

I want: spk validation smoke tests to also validate using config files and not just using flags

So that: I can be confident that config values are consistent and tested

Describe the solution you'd like:

Acceptance Criteria:

• [ ] Add a separate test of tests parallel to the current validation.sh scripts that tests the same commands, but utilizes spk init with a config file instead of using flags to pass in configurations.

Additional context:

Does this require updates to documentation?: yes

[andrebriggs]

@yradsmikham moving this back to TODO. Will probably skip this sprint

[samiyaakhtar]

Added a config file and spk init command in this PR https://github.com/CatalystCode/spk/pull/255, perhaps this file can be leveraged for this task, once merged?