Adding leading whitespaces in load_assignment on load-balancing#step2

Hello.
Can I share suggestion about the scenario of "Controlling load balancing policies" ?
I tried this scenario and got an error
> curl: (7) Failed to connect to localhost port 80: Connect

on step 3.
The reason was that the "load_assignment" copied in step2 does not have leading spaces.

Maybe most users will just copy it.
So I think it is better to put leading whitespaces in the load_assignment.
https://github.com/envoyproxy/katacoda-scenarios/blame/master/load-balancing/step2.md#L9-L24
Like
```
load_assignment:
cluster_name: targetCluster
endpoints:
- lb_endpoints:
- endpoint:
address:
socket_address:
address: 172.18.0.3
port_value: 80
load_balancing_weight: 90
- lb_endpoints:
- endpoint:
address:
socket_address:
address: 172.18.0.4
port_value: 80
```