fix(traefik): Update traefik how to URL

[Shrinks99]

Description
In my brief search to figure out why the items on https://truecharts.org/charts/description_list aren't listing the new train names, I stumbled upon this bit of the traefik help text that had a broken link. Seemed like an easy fix :)

⚙️ Type of change

• ⚙️ Feature/App addition
• 🪛 Bugfix
• ⚠️ Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 🔃 Refactor of current code

🧪 How Has This Been Tested?
I tried navigating to https://truecharts.org/charts/premium/traefik/how-to/ and it works!

✔️ Checklist:

• ⚖️ My code follows the style guidelines of this project
• 👀 I have performed a self-review of my own code
• #️⃣ I have commented my code, particularly in hard-to-understand areas
• 📄 I have made corresponding changes to the documentation
• ⚠️ My changes generate no new warnings
• 🧪 I have added tests to this description that prove my fix is effective or that my feature works
• ⬆️ I increased versions for any altered app according to semantic versioning
• I made sure the title starts with feat(chart-name):, fix(chart-name): or chore(chart-name):