In the Evergreen task logs, all but the job loggers that have a job number (e.g. Fixture and Hook loggers) have it in the 2nd position of the logging prefix delimited by colons. The job logger puts it in the 3rd place.

It'd be easier to parse the job number if the job logger could be prefixed with just "executor" instead of "executor:js_test" https://github.com/mongodb/mongo/blob/r3.5.4/buildscripts/resmokelib/testing/executor.py#L287