Fixing aws_dax_cluster example usage.
Fixing aws_dax_cluster example usage.

`cluster_id` is not a valid argument to the `aws_dax_cluster` resource.
nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,terraform-providers/terraform-provider-aws,nbaztec/terraform-provider-aws,terraform-providers/terraform-provider-aws,Ninir/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,nbaztec/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,Ninir/terraform-provider-aws,nbaztec/terraform-provider-aws