[python] fix uniqueItems validation tests (OpenAPITools#24092)

Pydantic 2 removed conlist(unique_items=True). The migration in
04fa53b kept OpenAPI arrays as lists because sets would lose ordering
and complicate JSON serialization, but left the old validation tests in
the synchronous and lazy-import samples.

Those tests do not require an exception, so they normally pass after
making a Petstore request and fail only when that request produces an
unrelated response validation error. Remove them from the Pydantic 2
samples.

Pydantic 1 still enforces uniqueItems. Make its test require the expected
validation error so a regression cannot silently pass.

Author: tamird

samples/openapi3/client/petstore/python-lazyImports/tests/test_api_validation.py

@@ -40,12 +40,6 @@ def setUpModels(self):
         self.pet.category = self.category
         self.pet.tags = [self.tag]
 
-    def test_set_param_validation(self):
-        try:
-            self.pet_api.find_pets_by_tags(["a", "a"])
-        except ValidationError as e:
-            self.assertTrue("the list has duplicated items" in str(e))
-
     def test_required_param_validation(self):
         try:
             self.pet_api.get_pet_by_id()  # type: ignore

samples/openapi3/client/petstore/python-pydantic-v1/tests/test_api_validation.py

@@ -47,10 +47,10 @@ def setUpModels(self):
         self.pet.tags = [self.tag]
 
     def test_set_param_validation(self):
-        try:
+        with self.assertRaisesRegex(
+            ValidationError, "the list has duplicated items"
+        ):
             self.pet_api.find_pets_by_tags(["a", "a"])
-        except ValidationError as e:
-            self.assertTrue("the list has duplicated items" in str(e))
 
     def test_required_param_validation(self):
         try:

samples/openapi3/client/petstore/python/tests/test_api_validation.py

@@ -40,12 +40,6 @@ def setUpModels(self):
         self.pet.category = self.category
         self.pet.tags = [self.tag]
 
-    def test_set_param_validation(self):
-        try:
-            self.pet_api.find_pets_by_tags(["a", "a"])
-        except ValidationError as e:
-            self.assertTrue("the list has duplicated items" in str(e))
-
     def test_required_param_validation(self):
         try:
             self.pet_api.get_pet_by_id()  # type: ignore