docs(courses): splitted resources from misc

[LuigiImVector]

What does this PR do?

Improve repo

For resources

Description

Split some resources from free-courses-en.md#misc, see #6518.
For some resources, I decided to create their own category because I found it important, despite the fact that they were only 2 resources.

Notes:

• Algorithm Design and Implementation doesn't exist
• Berkeley's CS 169: Software Engineering is a private video
• Bits: The Computer Science of Digital Information doesn't exist
• Embedded Software Safety (P. Koopman) doesn't exist, its link is a duplicate
• I deleted Functional Programming Principles in Scala because it is a part of Functional Programming in Scala Specialization
• Principles of Reactive Programming was a duplicate

Checklist:

• Read our contributing guidelines
• Search for duplicates.
• Include author(s) and platform where appropriate.
• Put lists in alphabetical order, correct spacing.
• Add needed indications (PDF, access notes, under construction)

Follow-up

• Check the status of GitHub Actions and resolve any reported warnings!

[eshellman]

Outstanding improvement