Document how to use the tool: rubycritic

[christinach]

Introduction

• Include rubycritic in our tools.

• Document how to use it effectively to help refactor/cleanup our code

• Provide examples from the requests form refactor work.

Acceptance criteria

• Update an existing markdown document or add a new one in the docs directory.

• It has introduction: Explains the goals and purpose of this documentation.

• It has a step by step guide: Provides the exact steps to guide the user on how to use this tool.

Additional acceptance criteria

• It includes references to the request form refactoring.
• It includes a link to the rubycritic github repo