Improve assertTransformsEqual

Make `assertTransformsEqual` produce a clearer failure
if two transforms have a corresponding endpoint that is generic
and has a different number of axes.

python/lsst/afw/geom/testUtils.py

@@ -974,6 +974,8 @@ def checkThen(self, fromName, midName, toName):
     def assertTransformsEqual(self, transform1, transform2):
         """Assert that two transforms are equal"""
         self.assertEqual(type(transform1), type(transform2))
+        self.assertEqual(transform1.fromEndpoint, transform2.fromEndpoint)
+        self.assertEqual(transform1.toEndpoint, transform2.toEndpoint)
         self.assertEqual(transform1.getFrameSet(), transform2.getFrameSet())
 
         fromEndpoint = transform1.fromEndpoint