Update k3d cluster create example

[brooke-hamilton]

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Description

This PR updates the recommended command to use when creating a k3d cluster by adding a parameter to the k3d cluster create command to disable the default load balancer. The default load balancer was conflicting with the load balancer deployed by Radius. See the issue reference linked below for details.

Note: traefik@server:0 was changed to traefik@server:* to indicate that all instances should be affected, not just the one at index zero.

Issue reference

Fixes: radius-project/radius#7637

[rynowak]

Just so I know what's going on ... does this command actually disable the built-in ingress + load balancer?

[rynowak]

/cc @Reshrahim @willtsai

[brooke-hamilton]

@rynowak K3d has an external load balancer that can be disabled, but the configuration in this PR does not do that. The external LB is an nginx instance that runs as a container and routes traffic from the host machine into the k3d cluster container. We could disable it by passing --no-lb to the k3d cluster create command, i.e. k3d cluster create --no-lib, however, we need the routing from the host machine into the cluster that is provided by the nginx container.

Inside the k3d cluster there is an internal load balancer called servicelb that distributes traffic. That is the one we are disabling with this configuration.