Here's the bottom of the log, which I suspect is what you need:
08:11:57 [WARNINGS] Parsing warnings in console log with parser Java Compiler (javac)
08:11:58 Archiving artifacts
08:11:59 Publishing Cobertura coverage report...
08:11:59 Publishing Cobertura coverage results...
08:12:01 Recording test results
08:12:02 Description set: Branch origin/feature.27.num-teams-per-judge
08:12:02 Email was triggered for: Success
08:12:02 Sending email for trigger: Success
08:12:02 Send to developers
08:12:02 Getting users from changeset
08:12:02 Get users from changeset - users.size() = 0
08:12:02 413: recipientAddresses.size() = 0
08:12:02 Setting 0 recipients
08:12:02 An attempt to send an e-mail to empty list of recipients, ignored.
08:12:02 Finished: SUCCESS
There was no new changeset for this build as it was triggered manually. So perhaps this is expected. I ran another job that always send to the default list of recipients and that one worked. I'll keep watching it and let you know if I have more trouble. I'll leave the debug one running on my opensource server.