Install additional Terraform dependencies in CTS container image

[joatmon08]

Description

Terraform requires additional dependencies such as git in order to download modules from git repositories or over SSH. Currently, the CTS container image does not include these dependencies. This means that go-getter cannot download the Terraform modules and CTS returns an error.

Use Cases

Any non-TFC/TFE use case running CTS in a container on an orchestrator and retrieving modules using git or ssh. TFC/TFE use their own runners, which have the dependencies already installed.

Alternative Solutions

• Run a sidecar container downloading the module and caching it in a volume for the CTS container. However, this is not ideal as new module requires both containers to reload.

• [Feature] Native Golang Git implementation #678

Additional context

This request happened because I tried to run CTS on Kubernetes and download a module from GitHub.