Example of what's happening:
https://logs.chromium.org/v/?s=chromium%2Fbuildbucket%2Fcr-buildbucket.appspot.com%2F8943213659355565120%2F%2B%2Fsteps%2Fcheck_for_undocumented_increase%2F0%2Fstdout

My futile attempt at getting the blank lines to appear:
https://cs.chromium.org/chromium/src/tools/binary_size/trybot_commit_size_checker.py?rcl=a9cd34ec652eeeef52d3326234c93df499cf54e7&l=64

Logs do have newlines when viewed via logdog command:
logdog cat chromium/buildbucket/cr-buildbucket.appspot.com/8943213659355565120/+/steps/check_for_undocumented_increase/0/stdout