Update React, MongoDB and Express to fix security and build issues

[sis0k0]

• fix(README): update the Node.js port to match the one used in the client
• fix: add missing alt text for MongoDB logo
• fix(loadEnvironments): match the source code to the article and the readme
• fix(server): update MongoDB driver to work with ES modules and promises. Update express to fix security vulnerabilities.
• fix(client): update to React 18 to fix OpenSSL issue
• fix(README): hardcode PORT in the server since it's hardcoded in the client

fixes #27

[joellord]

The code looks good. Client and server run well with Node.js v18.16.