Cleanup: add trailing commas for multi-line collections

Avoid accidentally missing commas between strings, see: T101020.
Also use single quotes for enum identifiers.

tests/python/bl_pyapi_idprop.py

@@ -218,7 +218,7 @@ class TestBufferProtocol(TestHelper, unittest.TestCase):
     def assertEqualMemviews(self, view1, view2):
         props_to_compare = (
             "contiguous", "format", "itemsize", "nbytes", "ndim",
-            "readonly", "shape", "strides", "suboffsets"
+            "readonly", "shape", "strides", "suboffsets",
         )
         for attr in props_to_compare:
             self.assertEqual(getattr(view1, attr), getattr(view2, attr))