Config map for storing Terraform files size limit

[josephsawaya]

According to this: https://kubernetes.io/docs/concepts/configuration/configmap/#motivation config maps can only hold 1 MiB, of information. This puts a hard limit on the total size of the Terraform files in a repository that we can support, since we're currently storing these in a config map using the terraform-generate plugin.

We should try finding alternate ways for the worker to access the Terraform files, to avoid this size limit issue.