sdist doesnt include sample

[jayvdb]

Trying to run the tests from the sdist uploaded to PyPI results in:

[   55s] + /usr/bin/python3 setup.py test
[   55s] running test
[   55s] running egg_info
[   55s] writing pytest_blame.egg-info/PKG-INFO
[   55s] writing dependency_links to pytest_blame.egg-info/dependency_links.txt
[   55s] writing entry points to pytest_blame.egg-info/entry_points.txt
[   55s] writing requirements to pytest_blame.egg-info/requires.txt
[   55s] writing top-level names to pytest_blame.egg-info/top_level.txt
[   55s] reading manifest file 'pytest_blame.egg-info/SOURCES.txt'
[   55s] writing manifest file 'pytest_blame.egg-info/SOURCES.txt'
[   55s] running build_ext
[   56s] test_sample (unittest.loader._FailedTest) ... ERROR
[   56s] tests.test_sample (unittest.loader._FailedTest) ... ERROR
[   56s] 
[   56s] ======================================================================
[   56s] ERROR: test_sample (unittest.loader._FailedTest)
[   56s] ----------------------------------------------------------------------
[   56s] ImportError: Failed to import test module: test_sample
[   56s] Traceback (most recent call last):
[   56s]   File "/usr/lib64/python3.7/unittest/loader.py", line 154, in loadTestsFromName
[   56s]     module = __import__(module_name)
[   56s]   File "/home/abuild/rpmbuild/BUILD/pytest-blame-0.1.7/tests/test_sample.py", line 2, in <module>
[   56s]     import sample
[   56s] ModuleNotFoundError: No module named 'sample'

fwiw, PyPI installable check-manifest can be used to ensure the sdist MANIFEST.in includes all files.