Remove file function wrapper from ssh_auth_key variable (#577)
Remove file function wrapper from ssh_auth_key variable (#577)

Co-authored-by: Morgante Pell <61671edc91680c186ace50c07efcb5b4afb03319@google.com>
terraform-google-modules/terraform-google-kubernetes-engine,terraform-google-modules/terraform-google-kubernetes-engine,terraform-google-modules/terraform-google-kubernetes-engine