Load sub-configs from composite configs (#34410)

* save/load sub-configs

* nit forgot these

* fix copies

* move test to common

* use dict for sub-configs

* add load-save-laod test

* clean up modeling check

* oops this are correct keys

* fix some tests, missed some composite configs

* this model was missed

tests/models/altclip/test_modeling_altclip.py

@@ -452,11 +452,20 @@ class AltCLIPModelTest(ModelTesterMixin, PipelineTesterMixin, unittest.TestCase)
 
     def setUp(self):
         self.model_tester = AltCLIPModelTester(self)
+        self.config_tester = ConfigTester(
+            self,
+            config_class=AltCLIPConfig,
+            has_text_modality=False,
+            common_properties=["projection_dim", "logit_scale_init_value"],
+        )
 
     def test_model(self):
         config_and_inputs = self.model_tester.prepare_config_and_inputs()
         self.model_tester.create_and_check_model(*config_and_inputs)
 
+    def test_config(self):
+        self.config_tester.run_common_tests()
+
     @unittest.skip(reason="Hidden_states is tested in individual model tests")
     def test_hidden_states_output(self):
         pass