Fix typo in test

Author: ethho

tests/test_relation.py

@@ -309,7 +309,7 @@ def relation_selector(attr):
     for name, rel in getmembers(schema, relation_selector):
         assert re.match(
             rel.tier_regexp, rel.table_name
-        ) == "Regular expression does not match for {name}".format(name=name)
+        ), "Regular expression does not match for {name}".format(name=name)
         for tier in tiers:
             assert issubclass(rel, tier) or not re.match(
                 tier.tier_regexp, rel.table_name