Fix the week_1 http server section

At **week_1/http/cmd/http_client/main.go**
this line 
```
getPostfix  =  "/notes/%d"
```

has to be 
```
getPostfix  =  "/notes/{id}"
```

because otherwise each time you client call the server it always get 404.

From go-chi docs:

```
// Regexp url parameters:
r.Get("/{articleSlug:[a-z-]+}", getArticleBySlug)                // GET /articles/home-is-toronto
```