Added maintainers.

As far as I can see at https://tools.wmflabs.org/forrestbot/forrestbot.err.txt this may be:

Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encodings'
Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]

The last activity registered in the logs was at 2019-03-06 19:47:35,945.

Thanks for taking a look at this. I migrated the bot to Stretch and Python 3 around that time, so that is likely the origin of the issue. I'll take a look in a bit more detail.