py-pytest needs py-setuptools_scm dependency?

[ryandesign (Ryan Carsten Schmidt)]

​From the buildbot:

Executing:  cd "/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_python_py-pytest/py34-pytest/work/pytest-3.1.1" && /opt/local/Library/Frameworks/Python.framework/Versions/3.4/bin/python3.4 setup.py --no-user-cfg build 
DEBUG: system:  cd "/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_python_py-pytest/py34-pytest/work/pytest-3.1.1" && /opt/local/Library/Frameworks/Python.framework/Versions/3.4/bin/python3.4 setup.py --no-user-cfg build 
Download error on https://pypi.python.org/simple/setuptools-scm/: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:600) -- Some packages may not be found!
Couldn't find index page for 'setuptools-scm' (maybe misspelled?)
Download error on https://pypi.python.org/simple/: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:600) -- Some packages may not be found!
No local packages or working download links found for setuptools-scm
Traceback (most recent call last):
  File "setup.py", line 99, in <module>
    main()
  File "setup.py", line 79, in main
    zip_safe=False,
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/distutils/core.py", line 108, in setup
    _setup_distribution = dist = klass(attrs)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/setuptools/dist.py", line 320, in __init__
    self.fetch_build_eggs(attrs['setup_requires'])
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/setuptools/dist.py", line 377, in fetch_build_eggs
    replace_conflicting=True,
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/pkg_resources/__init__.py", line 852, in resolve
    dist = best[req.key] = env.best_match(req, ws, installer)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/pkg_resources/__init__.py", line 1124, in best_match
    return self.obtain(req, installer)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/pkg_resources/__init__.py", line 1136, in obtain
    return installer(requirement)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/setuptools/dist.py", line 445, in fetch_build_egg
    return cmd.easy_install(req)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/setuptools/command/easy_install.py", line 667, in easy_install
    raise DistutilsError(msg)
distutils.errors.DistutilsError: Could not find suitable distribution for Requirement.parse('setuptools-scm')
Command failed:  cd "/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_python_py-pytest/py34-pytest/work/pytest-3.1.1" && /opt/local/Library/Frameworks/Python.framework/Versions/3.4/bin/python3.4 setup.py --no-user-cfg build 
Exit code: 1

[yan12125 (Chih-Hsuan Yen)]

In ba93bbc2ad6e9b279351f4eba8eba2d76f1764cb/macports-ports:

py-pytest: An attempt to fix build errors on OS X <= 10.11

Closes: #54310