python3-poetry-core: update 1.3.2 -> 1.4.0

Upstream has changed the tarball and the dir inside it to poetry_core
(with underscore).

License-Update: formatting, copyright years.

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>