test(settings): include preset fields in /ui-preferences pin assertion

Follow-up to the temperature & fan-speed presets feature — the
  TestUiPreferencesEndpoint.test_returns_expected_field_set test pins
  the exact set of fields the endpoint exposes (so adding a sensitive
  field by accident fails the assert). The 4 preset fields were added
  to _UI_PREFERENCE_FIELDS without updating the pin, breaking the full
  backend test run.

backend/tests/integration/test_settings_ui_preferences.py

@@ -88,6 +88,10 @@ class TestUiPreferencesEndpoint:
             "ams_temp_good",
             "ams_temp_fair",
             "bed_cooled_threshold",
+            "nozzle_temp_presets",
+            "bed_temp_presets",
+            "chamber_temp_presets",
+            "fan_speed_presets",
         }
         assert set(data.keys()) == expected