[cert] capitalize python class constants (#5080)

According to PEP8, constants should be written in all capital letters.

This commit capitalizes these constants:
- thread_cert.TestCase.topology
- thread_cert.TestCase.support_ncp

tests/scripts/thread-cert/Cert_5_2_05_AddressQuery.py

@@ -42,7 +42,7 @@ ROUTER_SELECTION_JITTER = 1
 
 
 class Cert_5_2_5_AddressQuery(thread_cert.TestCase):
-    topology = {
+    TOPOLOGY = {
         LEADER: {
             'mode':
                 'rsdn',