Update Terraform Readme (#457)
Update Terraform Readme (#457)

* Fix intial container images path in terraform services

* * update Terraform readme * update terraform version reference to 0.13.1 instead of 0.12 * fix terraform variable reference

Co-authored-by: Sherif Kozman <200f434064558b6198225d4da68bd89177824c6c@extremesolution.com>
google/exposure-notifications-verification-server,google/exposure-notifications-verification-server,google/exposure-notifications-verification-server,google/exposure-notifications-verification-server