EPIC: Clarify and Simplify logging #1355
Description
There are a few assumptions made by testground about logging that looks legacy / quite specific to the go-sdk,
The go-sdk writes json payloads to both the stdout and files like the run.out and run.err.
There are also different ways to process these outputs: the pretty.go is specific to local docker runner and might change test outcomes, the run.out files are collected by testground and used during testing, etc.
This EPIC aggregates discussion about this subject until we're ready to tackle this.