App.js cleanup

[JennaDalgety]

Ticket Number:

N/A

Describe The Problem Being Solved:

Cleanup of app.js file to remove extraneous code

Checklist For Submitter

• I have documented all new functionality
• I have screenshotted new UI changes and attached them to this PR

Checklist For Reviewer

• Code formatting/static analysis: is the code formatted properly? Does a linter/other form of static analysis reveal any issues? Does the code have appropriately low cyclomatic complexity?
• Code architecture: concerns are separated, code follows single-responsibility principle, code utilizes OOP, DRY code.
• Coding best practices: code avoids hard-coded variables, inefficient computations, reinventing the wheel when using frameworks. Code is well-commented and generally readable.
• Non-functional requirements: Code has accompanying tests (if using TDD). Programmer can easily explain decisions to reviewers.