Kokoro can't open file `kokoro_log_reader.py`

[dbolduc]

https://source.cloud.google.com/results/invocations/e503f1ca-d90a-4db8-95c3-ed9bb8c58539

/Users/kbuilder/.pyenv/versions/3.8.3/bin/python3: can't open file '/tmpfs/kokoro_log_reader.py': [Errno 2] No such file or directory

This occurence was on macOS. Note that the problem has also happened on Windows: https://github.com/googleapis/google-cloud-cpp/issues/4363#issuecomment-682315087

[scotthart]

https://source.cloud.google.com/results/invocations/0e8e8d40-eb55-4ede-ba15-dc3d857c5ecf

/Users/kbuilder/.pyenv/versions/3.8.3/bin/python3: can't open file '/tmpfs/kokoro_log_reader.py': [Errno 2] No such file or directory

[coryan]

No repeats in 90d, closing.