[hotfix] fix the logging fix that broke the build (#1940)

* [hotfix] fix the logging fix that broke the build

* Fixing tests

tests/core_tests.py

@@ -59,16 +59,20 @@ class CoreTests(SupersetTestCase):
             '/superset/slice/{}/?standalone=true'.format(slc.id))
         assert 'List Roles' not in resp
 
-    def test_endpoints_for_a_slice(self):
+    def test_slice_json_endpoint(self):
+        self.login(username='admin')
+        slc = self.get_slice("Girls", db.session)
+
+        resp = self.get_resp(slc.viz.json_endpoint)
+        assert '"Jennifer"' in resp
+
+    def test_slice_csv_endpoint(self):
         self.login(username='admin')
         slc = self.get_slice("Girls", db.session)
 
         resp = self.get_resp(slc.viz.csv_endpoint)
         assert 'Jennifer,' in resp
 
-        resp = self.get_resp(slc.viz.json_endpoint)
-        assert '"Jennifer"' in resp
-
     def test_admin_only_permissions(self):
         def assert_admin_permission_in(role_name, assert_func):
             role = sm.find_role(role_name)
@@ -466,6 +470,7 @@ class CoreTests(SupersetTestCase):
 
     def test_table_metadata(self):
         maindb = self.get_main_database(db.session)
+        backend = maindb.backend
         data = self.get_json_resp(
             "/superset/table/{}/ab_user/null/".format(maindb.id))
         self.assertEqual(data['name'], 'ab_user')
@@ -473,7 +478,6 @@ class CoreTests(SupersetTestCase):
         assert data.get('selectStar').startswith('SELECT')
 
         # Engine specific tests
-        backend = maindb.backend
         if backend in ('mysql', 'postgresql'):
             self.assertEqual(data.get('primaryKey').get('type'), 'pk')
             self.assertEqual(