Update free-programming-books-langs.md

[frustr8dlec]

The link give previous links to a closed-down site following two links you can get to the message that the data is now on the internet archive where you can then search for the book link provided points directly to the text

What does this PR do?

Improve repo by correcting a dead link

For resources

Description

Why is this valuable (or not)?

How do we know it's really free?

For book lists, is it a book? For course lists, is it a course? etc.

Checklist:

• [x ] Read our contributing guidelines.
• [x ] Search for duplicates.
• [x ] Include author(s) and platform where appropriate.
• [ ] Put lists in alphabetical order, correct spacing.
• [ ] Add needed indications (PDF, access notes, under construction).
• [ ] Used an informative name for this pull request.

Follow-up

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

[eshellman]

Thanks, and welcome to free-programming-books!