devel/py-apispec: Update to 4.4.1

• Use DISTVERSION instead of PORTVERSION

ChangLog: https://github.com/marshmallow-code/apispec/blob/dev/CHANGELOG.rst#441-2020-05-07

PR: 255740
Reported by: Goran Mekić <meka@tilda.center>
Approved by: dbaio, garga (mentors, implicit)