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

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

This patch contains the changes in 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 packge was the only change.

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

* gnu/packages/python.scm.scm: Remove inheriting Python 2 packages inheriting
  from a Python 3 package if adding python-setuptools respective
  python2-setuptools to [inputs], [native-inputs] and [propagated-inputs] have
  been the sole reason for inheriting. Remove now needless [properties]
  "python2-variant" where applicable.
  (python2-lockfile, python2-keyring, python2-dateutil-2,
  python2-parsedatetime, python2-pandas, python2-pyicu, python2-pytest-cov,
  python2-pytest-runner, python2-pytest-xdist, python2-cov-core,
  python2-itsdangerous, python2-numexpr, python2-q, python2-sqlalchemy-utils,
  python2-alembic, python2-beautifulsoup4, python2-msgpack, python2-ipaddress,
  python2-atomicwrites, python2-apipkg, python2-execnet, python2-pytest-cache,
  python2-wtforms, python2-mako, python2-waitress, python2-wsgiproxy2,
  python2-pyquery, python2-webtest, python2-translitcodec, python2-editor,
  python2-sphinxcontrib-programoutput, python2-psycopg2, python2-vobject,
  python2-flask, python2-cookies, python2-responses, python2-future,
  python2-ply, python2-wcwidth, python2-prompt-toolkit, python2-jedi,
  python2-requests-oauthlib, python2-pyserial, python2-nltk, python2-pymongo,
  python2-sh, python2-schematics, python2-publicsuffix, python2-publicsuffix2,
  python2-url, python2-freezegun, python2-cachecontrol, python2-lit,
  python2-pytest-pep8, python2-pytest-flakes, python2-glances,
  python2-betamax, python2-file, python2-flask-babel, python2-furl,
  python2-imagesize python2-orderedmultidict, python2-pycodestyle,
  python2-vcversioner, python2-graphql-core, python2-graphql-relay,
  python2-validictory): Remove neesless input "python2-setuptools", don't
  inherit, don't call strip-python2-variant.
  (python-lockfile, python-keyring, python-dateutil-2, python-parsedatetime,
  python-pandas, python-pyicu, python-pytest-cov, python-pytest-runner,
  python-pytest-xdist, python-cov-core, python-itsdangerous, python-numexpr,
  python-q, python-sqlalchemy-utils, python-alembic, python-beautifulsoup4,
  python-msgpack, python-ipaddress, python-atomicwrites, python-apipkg,
  python-execnet, python-pytest-cache, python-wtforms, python-mako,
  python-waitress, python-wsgiproxy2, python-pyquery, python-webtest,
  python-translitcodec, python-editor, python-sphinxcontrib-programoutput,
  python-psycopg2, python-vobject, python-flask, python-cookies,
  python-responses, python-future, python-ply, python-wcwidth,
  python-prompt-toolkit, python-jedi, python-requests-oauthlib,
  python-pyserial, python-nltk, python-pymongo, python-sh, python-schematics,
  python-nltk, python-publicsuffix2, python-cachecontrol, python-lit,
  python-pytest-pep8, python-pytest-flakes, python-glances, python-betamax,
  python-file, python-flask-babel, python-furl, python-imagesize,
  python-orderedmultidict, python-pycodestyle, python-vcversioner,
  python-graphql-core, python-graphql-relay, python-validictory): Remove
  "python2-variant" property.