www/py-tvdb_api: Update version 2.0=>3.0.2

• multimedia/py-tvnamer seems to fail specifically with python3.X as www/py-tvdb_api was not compatible with python 3.X

PR: 243386
Reported by: huber.georg@gmail.com
MFH: 2020Q2 (runtime fix)
Relnotes: https://github.com/dbr/tvdb_api/releases