openpilot isn't required for a car port PR (#33383)

* disable car docs diff

* mv routes.py

* bump opendbc
old-commit-hash: 48bceb2bbf

tools/car_porting/test_car_model.py

@@ -3,7 +3,7 @@ import argparse
 import sys
 import unittest # noqa: TID251
 
-from openpilot.selfdrive.car.tests.routes import CarTestRoute
+from opendbc.car.tests.routes import CarTestRoute
 from openpilot.selfdrive.car.tests.test_models import TestCarModel
 from openpilot.tools.lib.route import SegmentName