Test Cases

[barelyhuman]

Add test files for the following cases

• if in a git repository
• output if not in a git repository
• on a repo with just 1 commit and no tags
• on a repo with just 1 commit and 1 tag
• on a repo with 1 commit and multiple tags pointing to same commit
• on a repo with 1 tag and multiple commits
• on a repo with multiple tags and multiple commits