Integrations with Stripe for Payment Processing

[Jzhang0107]

• Finish unit tests for services, will need to mock Stripe Object responses
• Make front-end UI changes according to Jonathan's Figma here
• Add alerts to display errors to the user instead of console.log statements in the console
• Move priceIds at PricingPage (front-end) to .env file so we don't hardcode the IDs into the code
• Change all responses for fetch statements to be based off response string from back-end
• Clean up back-end code and ensure apiKey is being used properly