FrontEnd: Make the Menu bar sticky so when we scroll down we can always access it

[simonreddy2001]

Description

This PR makes the Menu bar sticky so when we scroll down we can always access it Please provide a short summary explaining what this PR is about.

Fixes #276

How to test?

npm run dev check menu bar is now sticky... Please provide a short summary how your changes can be tested?

Checklist

• [x] I have performed a self-review of my own code
• [x] I have followed the name conventions for CSS Classnames and filenames, Components names and filenames, Style filenames, if you are in doubt check the the project README.MD and here https://github.com/HackYourFuture-CPH/curriculum/blob/master/review/review-checklist.md
• [x] I have commented my code, particularly in hard-to-understand areas, if you code was simple enough mark the box anyway
• [x] I have made corresponding changes to the documentation, if you code was simple enough mark the box anyway
• [x] This PR is ready to be merged and not breaking any other functionality

[BikramRawat]

This PR is merged and closed after the approvals from the reviewers 👍