Add Unit Tests

Are you willing to contribute it (Yes/No): Yes

**Describe the feature and the current behavior/state.**
Add unit tests so that we can setup github actions to ensure commits don't break existing functionality.

**Will this change the current API? How?**
No
**Who will benefit with this feature?**
Everyone that uses pgp-create as it helps ensure the stability as updates are committed.
**Miscellaneous Information**

No files, test entry points, or test framework are identified in the issue. Start by reading the repository structure and current JavaScript functionality, then determine what behavior needs unit coverage and how GitHub Actions should run it; done means the relevant existing behavior is covered and the checks run successfully in CI.

Written by the indexing model from the issue text.