Python 3 Fix: use six.reraise
Python 3 Fix: use six.reraise

Use six.reraise to transfer exceptions across threads instead of the
old python 2 syntax.

Change-Id: Ie8d401811e12f9199a6fa88100ed2acd9385343c

gooddata/zuul,gooddata/zuul,gooddata/zuul,gooddata/zuul,gooddata/zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,wikimedia/integration-zuul