Bug#972423: b-d's on python3-all-dev, but only builds for the default python3

[Matthias Klose]

Package: src:stimfit
Version: 0.16.0-1

stimfit b-d's on python3-all-dev, but only builds for the default python3
version.

Either b-d on python3-dev, or build for all supported python3 versions.