Fix backend for Honeybadger 2

Honeybadger 2 is multi-threaded, meaning when you call
Honeybadger.notify it returns immediately.  Under Resque the worker
process where the failure is handled is killed as soon as it finishes,
so we need to resync threads.

Also removed deprecated configure block, and added more context.

Note that as of my testing tags are not showing up correctly, but
I think this is a Honeybadger bug as I verfied it is correctly making
it into the json output.

[#83270304]
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