Hypothesis for Python - version 4.44.5

This patch disables our pytest plugin when running on versions of
pytest before 4.3, the oldest our plugin supports. Note that at time
of writing the Pytest developers only support 4.6 and later!

Hypothesis tests using "@given()" work on any test runner, but our
integrations to e.g. avoid example database collisions when combined
with "@pytest.mark.parametrize" eventually drop support for obsolete
versions.

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