ref(builder): remove python and jq from the builder script

Replaced by small go apps.

This is the first step. The next one is replace the builder script completely and use go using something like https://github.com/codeskyblue/go-sh 
So if we get an error response from the controller like `failed to launch containers`, this response is going to be placed in the builder. Not sure if we want to print our own custom message vs. dumping the error from the controller as we do now.