The duration can be 10:01 if the original task call happened a split
second before the faketime fixation of +10 minutes.
Use more relaxed regular expresison to check.
This commit updates all tests to enforce the Python3 executable. This is
necessary because the `assertRegex` function we use was renamed to this
name only in Python 3.2 [1]
For reference:
s;/usr/bin/env python;/usr/bin/env python3;g
[1]: https://docs.python.org/3/library/unittest.html#unittest.TestCase.assertRegex