Add cors_origins variable and pass to image
As required for https://gitlab.developers.cam.ac.uk/uis/devops/iam/activate-account/infrastructure/-/issues/5 and based off changes made in uis/devops/ucam-observe/ucam-observe-remote-server!6 (merged), adds cors_origin
variable to allow the client projects to specify allowed CORS requests origins to the log server when deploying.