Hot dog tutorial encourages hard coding credentials

**Problem**

Hot dog tutorial, in explaining the client/server split, suggests that it's good practice to hardcode credentials in server code.

**Steps To Reproduce**

Steps to reproduce the behavior:

- https://dioxuslabs.com/learn/0.6/guide/backend#the-clientserver-split

**Expected behavior**

Either use a different example, or add a note linking to best practices for handling credentials explaining you shouldn't do this anyway. Preferably the former for lack of ambiguity

**Screenshots**

**Environment:**

- Dioxus version: 0.6.3

**Questionnaire**

I don't have time to fix this right now, but maybe later.