python3-attrs: disable Hypothesis deadline

python3-attrs: disable Hypothesis deadline

The deadline is by default 200ms, but this is intended to be useful to
the developer and not necessarily recommended for heavily loaded CI
systems. Avoid warnings by disabling the deadline completely.

https://github.com/HypothesisWorks/hypothesis/issues/3713
https://hypothesis.readthedocs.io/en/latest/settings.html#hypothesis.settings.deadline
https://lists.openembedded.org/g/openembedded-core/topic/104640034#196437
https://github.com/python-attrs/attrs/pull/1252

Fixes:
"""
Unreliable test timings! On an initial run, this test took 268.29ms,
which exceeded the deadline of 200.00ms, but on a subsequent run it
took 2.63 ms, which did not. If you expect this sort of variability in
your test timings, consider turning deadlines off for this test by
setting deadline=None.
"""

[YOCTO #15350]

Signed-off-by: Tim Orling <tim.orling@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>