make polycyclic test on checkSiblingsForParents

Author: KEHANG

testing/databaseTest.py

@@ -116,12 +116,11 @@ def test_thermo(self):
             self.compat_func_name = test_name
             yield test, group_name
 
-            if group_name != 'polycyclic':
-                test = lambda x: self.general_checkSiblingsForParents(group_name, group)
-                test_name = "Thermo groups {0}: sibling relationships are correct?".format(group_name)
-                test.description = test_name
-                self.compat_func_name = test_name
-                yield test, group_name
+            test = lambda x: self.general_checkSiblingsForParents(group_name, group)
+            test_name = "Thermo groups {0}: sibling relationships are correct?".format(group_name)
+            test.description = test_name
+            self.compat_func_name = test_name
+            yield test, group_name
 
             test = lambda x: self.general_checkCdAtomType(group_name, group)
             test_name = "Thermo groups {0}: Cd atomtype used correctly?".format(group_name)