#47 - terraform 1.2.8 breaks without SA removal - critical fix

[fmichaelobrien]

see full clean org testing in #47

[fmichaelobrien]

Summary: the unsupported argument error - is an expected result of an API change
Fix is usually to adapt the module or inherit the variable - here is is just to remove the reference in projects.tf

admin_@cloudshell:~/cloudshell_open/accelerators_accelerateurs-gcp/deployment-templates/Terraform/guardrails/1-guardrails (ggz-seed-project)$ terraform apply -var-file variables.tfvar
╷
│ Error: Unsupported argument
│
│   on projects.tf line 5, in module "administration":
│    5:   impersonate_service_account = var.terraform_service_account
│
│ An argument named "impersonate_service_account" is not expected here.