[tests/cocom] Add test for get_identities

Test was missing for get_identities function in cocom.py
This commit adds the test to check for the return value
of every item.

Signed-off-by: sevagenv <sevagenv@gmail.com>

tests/test_cocom.py

@@ -42,6 +42,14 @@ def test_has_identites(self):
         enrich_backend = self.connectors[self.connector][2]()
         self.assertFalse(enrich_backend.has_identities())
 
+    def test_get_identities(self):
+        """Test value of get_identities method"""
+
+        identities = []
+        enrich_backend = self.connectors[self.connector][2]()
+        for item in self.items:
+            self.assertEqual(enrich_backend.get_identities(item), identities)
+
     def test_items_to_raw(self):
         """Test whether JSON items are properly inserted into ES"""