Fixed broken links in Linux, Networking, and CodeIgniter tutorial sections

[thenameisanjalii]

What does this PR do?

Add resource(s) | Remove resource(s) | Add info | Improve repo

IMPORTANT

• Read our contributing guidelines.
• Is this a revision of a previously submitted PR? If so, STOP! Go back, reopen the PR, and add commit(s) the branch you previously submitted. Please don't make the job of reviewing more difficult by hiding previous work.

Description

Fixed broken links in Linux, Networking, and CodeIgniter tutorial sections

Changes:

• Replaced non-functional video playlist URLs with verified, active resources
• All updated links tested and confirmed accessible
• Maintained alphabetical ordering and proper formatting
• Ensured correct author attribution

Checklist:

• 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).
• Used an informative name for this pull request.

[thenameisanjalii]

Hi! I've updated the broken links in Linux, Networking, and CodeIgniter sections with verified, working resources. Could you please review this PR? Thanks! @eshellman

[rdhyee]

Hi @thenameisanjalii! Thanks for fixing these broken links! 👋

Verification:

• ✅ Fixed broken Linux course link (WsCube Tech → Cloud Tech Burner)
• ✅ Fixed broken Networking link (Network Kings → Neso Academy)
• ✅ Fixed broken CodeIgniter tutorial link (Technical Suneja → Heavy Coding)
• ✅ All linter checks passing
• ✅ Proper format and replacements

Excellent work finding working replacements for all three dead links. This kind of maintenance is invaluable! Ready to merge!

Welcome to the project! 🎉

[thenameisanjalii]

Thankyou @rdhyee , your appreciation means a lot to me

I have recently created a pull request for another issue too, it would be very helpful if you could review it and tell your thoughts.
Pull request link - #12744