Skip another pickle test if dill isn't installed.

[EdwardBetts]

Fixes this test failure when dill isn't installed:

ERROR: test_config_pickle (__main__.HumanNamePythonTests)
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Traceback (most recent call last):
  File "tests.py", line 82, in test_config_pickle
    self.assertTrue(dill.pickles(C))
AttributeError: 'bool' object has no attribute 'pickles'

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Ran 261 tests in 0.150s

FAILED (errors=1, skipped=1, expected failures=11)