Implementation of Kazakh translation

[chprince11]

Checklist:

• I have read freeCodeCamp's contribution guidelines.
• My pull request has a descriptive title (not a vague title like Update index.md)
• My pull request targets the main branch of freeCodeCamp.

Closes #947

• This PR report highlights the successful integration of Kazakh translation capabilities into our platform, along with the resolution of a critical issue identified by the Kazakh-speaking community.

Thank you! 🙂

[chprince11]

Error Fixed ✅

| Error ❌

• Can't find the language code in iso639.txt, which means the code is not valid ISO 639 language code.

| Approach to solve✅

• Added the Debug statements in the script to print out the content of iso639.txt, in order to figure out what's going wrong.
• Converted all list of the ISO 639 language codes from Wikipedia to uppercase using tr '[:lower:]' '[:upper:]'.
• Changed the invalid language code on my local branch , and then pushed it back to the remote repository in order to support all ISO 639 language codes.

[chprince11]

I have changed the language code for some README.md as it is showing me the error in the process of workflow. So, I need to do the PR again and just let the error be there. What should I do? Can anyone review it and let me know? Thank you 😊