FWIW, they had said that they didn't write it originally and had found it "somewhere on the Internet". Searching for "pid: .pipeline.id, tid: .id, ts" has turned up this, which might be the original source (if it is in fact the same script as I am on a phone and didn't 100% check):
https://gitlab.com/gitlab-org/gitlab/-/issues/236018#note_39...