Alternative ways to speed up "collie foundation docs"

[JohannesRudolph]

After the unsucessful attempt of enabling fast output collection via parallel terraform invocations (see #271) I've been looking into alternative ways of speeding up the workflow with terragrunt.

Here are some avenues I've tried:

• Terragrunt has some fundamental performance optimization potential for complex multi-module configurations, see https://github.com/gruntwork-io/terragrunt/issues/2202
• I tried looking into caching outputs, however finding a good cache key is non trivial. I looked into abusing .terragrunt-source-version but it seems that any change to one platform module also changes hashes for other modules (verify using ,find . -type f -name ".terragrunt-source-version" -exec sh -c 'echo {}; cat {};echo ""' \;). so this would provide little use in practice