Add CLI commands test suite

[vhadianto]

From a brief research, there doesn't seem an idiomatic way to do this:

spf13/cobra#770

Also found these:
https://nayaktapan37.medium.com/testing-cobra-commands-in-golang-ca1fe4ad6657
https://gianarb.it/blog/golang-mockmania-cli-command-with-cobra
https://g14a.dev/posts/Testing-Cobra-Subcommands/

[github-actions]

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[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 30 days.

[github-actions]

This issue was closed because it has been stalled for 90 days with no activity.