Fix memory/cpu typo in gke cluster module

[heaton-dev]

Resolves:

> terraform  apply  /var/tmp/1000/terraform/26c67a5d-6df1-48ef-b802-69c0ae4a0209.tfplan
module.cluster.google_container_cluster.cluster: Creating...
╷
│ Error: googleapi: Error 400: Duplicate resource: cpu., badRequest
│ 
│   with module.cluster.google_container_cluster.cluster,
│   on fabric/modules/gke-cluster/main.tf line 17, in resource "google_container_cluster" "cluster":
│   17: resource "google_container_cluster" "cluster" {
│ 
╵

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[ludoo]

Thanks for this!