TSR "test_sample_xyzrpy" unit test fails

[mkoval]

@jeking04 reported this earlier and I was able to replicate it. I suspect that this test never passed:

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FAIL: test_sample_xyzrpy (tests.tsr.test_tsr.TsrTest)
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Traceback (most recent call last):
  File "/homes/mkoval/herb-ws/src/prpy/tests/tsr/test_tsr.py", line 21, in test_sample_xyzrpy
    self.assertTrue(numpy.all(s >= Bw[:, 0]))
AssertionError: False is not true

@psigen Can you take a look at this?