Chore: Documentation For How to Set the Project Up

[KevinMulhern]

Description

We need instructions in the root README on what the student needs to do to set the project up

Acceptance Criteria

1. The README should include an introduction explaining what the repo is for and what it contains
2. The README should include an installations section explaining how to set the project up on their machine, git clone, running bundle install etc.
3. The README should include a section on how the student can run their first test.

Additional Notes

Our older archived test first ruby repo might be a good example to follow: https://github.com/TheOdinProject/learn_ruby