Store tfstate onto separate infra project

[andrewperlas]

So that terraform apply -destroy doesn't affect the storage that the .tfstate file will live in, I have created a separate GCP project to store the file. Steps to complete this task.

• [x] Create separate GCP infra project
• [x] Create storage bucket to store tfstate
• [x] Set up Workload Identity Federation between this repo and the new project
  • [x] Create Pool
  • [x] Create Provider
  • [x] Create Service Account
  • [x] Assign Service Account the correct permissions
  • [x] Allow authentications from the Workload Identity Provider to impersonate the Service Account
• [x] Migrate .tfstate to GCP bucket
• [x] Modify existing Terraform code to refer to new infra storage bucket as the backend tfstate

[andrewperlas]

Tried setting this up, but wasn't sure how the GA workflow file would be able to refer to two separate projects for all the terraform jobs. For now, storing the .tfstate file in a bucket within the same GCP project. Can revisit this in the future.