Service accounts are shared between deployments:

[BryceBeagle]

Error: Error creating service account: googleapi: Error 409: Service account terraform-artifact-registry-sa already exists within project projects/shortcake-dev.
│ Details:
│ [
│   ***
│     "@type": "type.googleapis.com/google.rpc.ResourceInfo",
│     "resourceName": "projects/shortcake-dev/serviceAccounts/terraform-artifact-registry-sa@shortcake-dev.iam.gserviceaccount.com"
│   ***
│ ]
│ , alreadyExists
│ 
│   with module.docker_image.google_service_account.artifact_registry_image_sa,
│   on modules/docker_image/main.tf line 21, in resource "google_service_account" "artifact_registry_image_sa":
│   21: resource "google_service_account" "artifact_registry_image_sa" ***
│ 
╵

They should be unique per deployment