Our golden unit testing is broken when running with bazel/trying to update tests locally (e.g. bazel test +my_golden_test), since the buildscripts/golden_test.py utility: # sets up an environment variable pointing to a config file

1. sets up a config file which updates the expected output directory for the test

But bazel doesn't propagate environment variable defs when it executes.

 
Bazel also updates the current running dir, this means we can't keep using relative paths for test output directories. Not sure how to get their absolute paths though, since it requires knowing what the absolute path of the source directory is (somehow).
 
I'd be surprised if this only affects local runs, but I would expect this to generate evergreen build failures if it did affect evergreen runs.