update README

[endrasww]

Please fill in this pull request template before submitting

1. This pull request resolves #121

2. Description

Update the README file to include previously unlisted tutorials.

Note: mongodb.py and string-reversal.py are not included because they are still an empty template.

3. Fill in checklist by marking [x]

• [ x] I've read the CONTRIBUTING.md
• [ x] I was assigned to this issue
• [ x] My code is formatted using required linting
• [ x] I've run my code locally and checked it works

[sabderemane]

Thank you for your contribution @endrasww ! 🔥

[endrasww]

You are welcome. Thanks for the opportunity @sabderemane