gnu: Remove python-setuptools and python2-setuptools from inputs (part 4a)

gnu: Remove python-setuptools and python2-setuptools from inputs (part 4a)

This patch contains the changes for all modules beside python.scm where
setuptools are used in an inherited package and removing this input also
removes the need for inheriting the package. This is the case if adding
setuptools in the inherited package was the only change.

Change this to not inherit and remove the new needless call to
"strip-python2-variant (if applicable).

* gnu/packages/bioinformatics.scm (python-biopython, python2-biopython,
  python-twobitreader, python2-twobitreader,
  python-plastid, python2-plastid,
  python2-pybigwig,
  python2-screed,
  sra-tools): No longer "inherit" Python 2 packages
  inheriting from a Python 3 package if the sole reason for inheriting was
  adding python-setuptools respective python2-setuptools to [inputs],
  [native-inputs] or [propagated-inputs]. Remove now needless [properties]
  "python2-variant" where applicable.
* gnu/packages/django.scm (python-pytest-django, python2-pytest-django,
  python-django-filter, python2-django-filter): Likewise.
* gnu/packages/gnupg.scm (python2-pygpgme): Likewise.
* gnu/packages/mail.scm (python-mailmanclient, python2-mailmanclient):
  Likewise.
* gnu/packages/mpd.scm (python-msp, python2-mpd2): Likewise.
* gnu/packages/music.scm (python-pylast, python2-pylast): Likewise.
* gnu/packages/openstack.scm (python-requests-mock, python2-requests-mock,
  python2-git-review): Likewise.
* gnu/packages/password-utils.scm (python2-bcrypt): Likewise.
* gnu/packages/protobuf.scm (python-protobuf, python2-protobuf): Likewise.
* gnu/packages/statistics.scm (python-patsy, python2-patsy): Likewise.
* gnu/packages/web.scm (python2-feedparser): Likewise.