docs: don't set CLUSTER_NAME in envvars.txt because it's set with the -c

Signed-off-by: Andrew Sy Kim <[email protected]>

docs/getting_started.md

@@ -84,7 +84,6 @@ export SSH_AUTHORIZED_KEY='ssh-rsa AAAAB3N...'      # (optional) The public ssh
 
 # Kubernetes configs
 export KUBERNETES_VERSION='1.13.6'        # (optional) The Kubernetes version to use, defaults to 1.13.6
-export CLUSTER_NAME='management-cluster'  # (optional) The name for the management cluster, defaults to "capv-mgmt-example"
 export SERVICE_CIDR='100.64.0.0/13'       # (optional) The service CIDR of the management cluster, defaults to "100.64.0.0/13"
 export CLUSTER_CIDR='100.96.0.0/11'       # (optional) The cluster CIDR of the management cluster, defaults to "100.96.0.0/11"
 EOF