Remove unused hologram-dependent unit tests

tests/unit/utils.py

@@ -7,7 +7,6 @@
 from unittest import TestCase, mock
 
 from dbt.config.project import PartialProject
-from hologram import ValidationError
 
 
 def normalize(path):
@@ -121,33 +120,6 @@ def inject_adapter(value, plugin):
     FACTORY.adapters[key] = value
 
 
-class ContractTestCase(TestCase):
-    ContractType = None
-
-    def setUp(self):
-        self.maxDiff = None
-        super().setUp()
-
-    def assert_to_dict(self, obj, dct):
-        self.assertEqual(obj.to_dict(), dct)
-
-    def assert_from_dict(self, obj, dct, cls=None):
-        if cls is None:
-            cls = self.ContractType
-        self.assertEqual(cls.from_dict(dct), obj)
-
-    def assert_symmetric(self, obj, dct, cls=None):
-        self.assert_to_dict(obj, dct)
-        self.assert_from_dict(obj, dct, cls)
-
-    def assert_fails_validation(self, dct, cls=None):
-        if cls is None:
-            cls = self.ContractType
-
-        with self.assertRaises(ValidationError):
-            cls.from_dict(dct)
-
-
 def generate_name_macros(package):
     from dbt.contracts.graph.parsed import ParsedMacro
     from dbt.node_types import NodeType