fix(curriculum): replace flaky solution

[gikf]

Checklist:

• I have read and followed the contribution guidelines.
• I have read and followed the how to open a pull request guide.
• My pull request targets the main branch of freeCodeCamp.
• I have tested these changes either locally on my machine, or GitPod.

Closes #53140

---

• Changes solution to one using Markov chain.
• Improves solution result consistency and efficiency (I'm seeing 4x-25x speedup depending on test case).
• Don't hesitate to ask if something isn't clear. I can't promise I will be able to explain all the math behind it, but what's happening - yes.

[moT01]

LGTM ❓🙃 🎉

Did you write this @gikf?

[gikf]

@moT01,

Yeah, any concerns?

[moT01]

nope. It just looks impressive.