robustify the #577 tests

Code/GraphMol/PartialCharges/Wrap/testPartialCharges.py

@@ -117,7 +117,11 @@ class TestCase(unittest.TestCase):
         """ tests handling of Github issue 577 """
         m1 = Chem.MolFromSmiles('CCO')
         from locale import setlocale, LC_NUMERIC
-        setlocale(LC_NUMERIC, "de_DE")
+        try:
+            setlocale(LC_NUMERIC, "de_DE")
+        except:
+            # can't set the required locale, might as well just return
+            return
         rdPartialCharges.ComputeGasteigerCharges(m1)
         for at in m1.GetAtoms():
             float(at.GetProp('_GasteigerCharge'))