package/libnatpmp: bump version to 20230423
Updated license hash due to reformat of license file:
https://github.com/miniupnp/libnatpmp/commit/d89c1db679c09dbe71ba58b012e4afae2de06376
Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>