fix: Fix UPI integration test (#548)

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# Description
<!-- Briefly describe the motivation for the change. Please include
illustrations where appropriate. -->
In recent [PR](#544)
accidentally update env variable for transformer that fail the test as
the infer method is not correct for upi http predictor. This PR fix the
infer method and parameterize the test whether it is using http
predictor or not
# Modifications
<!-- Summarize the key code changes. -->
Update pyfunc_upi_integration_test.py
# Tests
<!-- Besides the existing / updated automated tests, what specific
scenarios should be tested? Consider the backward compatibility of the
changes, whether corner cases are covered, etc. Please describe the
tests and check the ones that have been completed. Eg:
- [x] Deploying new and existing standard models
- [ ] Deploying PyFunc models
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# Checklist
- [ ] Added PR label
- [ ] Added unit test, integration, and/or e2e tests
- [ ] Tested locally
- [ ] Updated documentation
- [ ] Update Swagger spec if the PR introduce API changes
- [ ] Regenerated Golang and Python client if the PR introduces API
changes

# Release Notes
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```release-note

```

python/sdk/test/pyfunc_upi_integration_test.py

@@ -10,6 +10,7 @@
 import xgboost as xgb
 from caraml.upi.utils import df_to_table, table_to_df
 from caraml.upi.v1 import type_pb2, upi_pb2, upi_pb2_grpc, variable_pb2
+from google.protobuf.json_format import MessageToDict, ParseDict
 from merlin.deployment_mode import DeploymentMode
 from merlin.endpoint import Status
 from merlin.model import ModelType, PyFuncModel
@@ -63,7 +64,13 @@ class SimpleForwarder(PyFuncModel):
     target_name = "probability"
 
     def infer(self, request: dict, **kwargs):
-        return request
+        upi_request = upi_pb2.PredictValuesRequest()
+        ParseDict(request, upi_request)
+        upi_response = upi_pb2.PredictValuesResponse(
+            prediction_result_table=upi_request.prediction_table,
+            target_name=self.target_name,
+        )
+        return MessageToDict(upi_response)
 
     def upiv1_infer(
         self, request: upi_pb2.PredictValuesRequest, context: grpc.ServicerContext
@@ -107,12 +114,14 @@ def test_deploy(integration_test_url, project_name, use_google_oauth, requests):
 
 @pytest.mark.pyfunc
 @pytest.mark.integration
+@pytest.mark.parametrize("upi_http_predictor", [False, True])
 def test_pyfunc_with_standard_transformer(
-    integration_test_url, project_name, use_google_oauth, requests
+    integration_test_url, project_name, upi_http_predictor, use_google_oauth, requests
 ):
     merlin.set_url(integration_test_url, use_google_oauth=use_google_oauth)
     merlin.set_project(project_name)
-    merlin.set_model("pyfunc-upi-std", ModelType.PYFUNC)
+    model_name = "pyfunc-upi-std-http" if upi_http_predictor else "pyfunc-upi-std"
+    merlin.set_model(model_name, ModelType.PYFUNC)
 
     undeploy_all_version()
     with merlin.new_model_version() as v:
@@ -125,10 +134,12 @@ def test_pyfunc_with_standard_transformer(
     transformer_config_path = os.path.join(
         "test/transformer", "upi_standard_transformer_no_feast.yaml"
     )
+
+    upi_http_enabled_val = "true" if upi_http_predictor else "false"
     transformer = StandardTransformer(
         config_file=transformer_config_path,
         enabled=True,
-        env_vars={"PREDICTOR_UPI_HTTP_ENABLED": "true"},
+        env_vars={"PREDICTOR_UPI_HTTP_ENABLED": upi_http_enabled_val},
     )
     endpoint = merlin.deploy(v, transformer=transformer, protocol=Protocol.UPI_V1)