test: Add tests for userObject functionality

[ericahagle]

Description

• Includes a new test file for unit testing our (non-DOM-related) base functions
  • scripts-test.js
• Includes a new file to house the base functions
  • scriptDefinitions.js
• Removes base functions from the scripts.js file and adds them to the scriptDefinitions.js file
  • The scripts.js file shouldn't contain any function definitions—it should be the file where we use the base functions
• Add tests for generateRandomUserID function
• Add tests for selectCurrentUser function
• Clean up files

Contributors

@ericahagle

Notes

• This PR is catch up because the tests weren't written along with the implementation code for these particular functions
  • Going forward, we'll be including the tests in the PRs for the functions themselves
• Before starting on the actual tests for the functions, I needed to update UserRepository-test.js so that it actually works, so that is also included in this PR
• This PR also includes minor formatting fixes

Checklist

• [x] My PR has an appropriately descriptive and concise title.
• [x] My PR denotes any/all team members who contributed to it.
• [x] My code follows the Turing Style Guides and best practices.
• [x] I ran the code locally and verified that there are no visible errors, and all tests pass.
• [x] test: My PR clearly describes what tests I'm adding/updating and why. (if applicable)