Fixed tests

Author: syrusakbary

graphql/validation/tests/test_validation.py

@@ -1,7 +1,7 @@
 from graphql import parse, validate
 from graphql.utils.type_info import TypeInfo
 from graphql.validation.rules import specified_rules
-from graphql.validation.validate import visit_using_rules
+from graphql.validation.validation import visit_using_rules
 
 from .utils import test_schema