make TestRunGreedyIncrementalModel not use a hardcoded user_id

This test is failing because it expects shankari_2016-06-20.expected_confirmed_trips to have a specific UUID, which is hardcoded in the test.

This came up the last time these "expected" snapshots were re-generated: 3c52375

I think it will be annoying to keep replacing the user_id every time the expected outputs change. So I just reworked the test to use whatever user_id is in the file rather than some arbitrary one

emission/tests/modellingTests/TestRunGreedyIncrementalModel.py

@@ -32,9 +32,15 @@ def setUp(self):
         logging.basicConfig(
             format='%(asctime)s:%(levelname)s:%(message)s',
             level=logging.DEBUG)
+
+        # read test trips from a test file
+        input_file = 'emission/tests/data/real_examples/shankari_2016-06-20.expected_confirmed_trips'
+        with open(input_file, 'r') as f:
+            test_trips_json = json.load(f, object_hook=esj.wrapped_object_hook)
+            test_trips = [ecwe.Entry(r) for r in test_trips_json]
+        logging.debug(f'loaded {len(test_trips)} trips from {input_file}')
 
-        # emission/tests/data/real_examples/shankari_2016-06-20.expected_confirmed_trips
-        self.user_id = uuid.UUID('aa9fdec9-2944-446c-8ee2-50d79b3044d3')
+        self.user_id = test_trips[0]['user_id'] # all trips within the test file have the same user_id
         self.ts = esta.TimeSeries.get_time_series(self.user_id)
         self.new_trips_per_invocation = 3
         self.model_type = eamumt.ModelType.GREEDY_SIMILARITY_BINNING
@@ -52,15 +58,8 @@ def setUp(self):
         if len(existing_entries_for_user) != 0:
             raise Exception(f"test invariant failed, there should be no entries for user {self.user_id}")
 
-        # load in trips from a test file source
-        input_file = 'emission/tests/data/real_examples/shankari_2016-06-20.expected_confirmed_trips'
-        with open(input_file, 'r') as f:
-            trips_json = json.load(f, object_hook=esj.wrapped_object_hook)
-            trips = [ecwe.Entry(r) for r in trips_json]
-        logging.debug(f'loaded {len(trips)} trips from {input_file}')
-        self.ts.bulk_insert(trips)
-
-        # confirm write to database succeeded
+        # write trips to database and confirm that they were written
+        self.ts.bulk_insert(test_trips)
         self.initial_data = list(self.ts.find_entries([esdatq.CONFIRMED_TRIP_KEY]))
         if len(self.initial_data) == 0:
             logging.debug(f'test setup failed while loading trips from file')