test(cmds): add unit tests for cobra cmds

[tthvo]

Description

This added unit tests for cobra cmds. As a side effect, these cmds are refactored to be created and initialized from function calls, replacing top-level variable and init function.

Other changes:

• Refactored formatter tests to reflect its use cases (i.e. behaviors).

Related to #7

Type of change

Please select the type of change(s) this PR introduces:

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] Code clean up
• [x] Tests
• [ ] Documentation update

Checklist

• [x] I have read the Contributing Guidelines document
• [x] I have include additional documentations if the PR includes user-facing changes
• [x] I have signed my commits. See references for more details

Additional Information

N/A