package/python-aiomqtt: use poetry setup type
Aiomqtt uses Poetry. The only difference between poetry and generic
pep517 is the host-python-poetry-core dependency, and this got pulled in
as an indirect dependency of host-python-poetry-dynamic-versioning so
far. So the build was not actually failing, but it's better to be
correct.
Signed-off-by: Fiona Klute (WIWA) <fiona.klute@gmx.de>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>