test: Change call counts with model back as default.

We don't call the modulestore or update the cache here now that we are
backed by the database model.  Previously the cache would change because
the `_encode_root_cache_key` function in `BlockStructureStore` class
used the `BlockstoreBlockData.VERSION` as a part of the cache key when
the data was not being cached in a DB model.

openedx/core/djangoapps/content/block_structure/tests/test_manager.py

@@ -208,8 +208,8 @@ def test_get_collected_transformer_version(self):
     def test_get_collected_structure_version(self):
         self.collect_and_verify(expect_modulestore_called=True, expect_cache_updated=True)
         BlockStructureBlockData.VERSION += 1
-        self.collect_and_verify(expect_modulestore_called=True, expect_cache_updated=True)
-        assert TestTransformer1.collect_call_count == 2
+        self.collect_and_verify(expect_modulestore_called=False, expect_cache_updated=False)
+        assert TestTransformer1.collect_call_count == 1
 
     def test_clear(self):
         self.collect_and_verify(expect_modulestore_called=True, expect_cache_updated=True)