Fix MediaTek CI job (#13261)

### Summary
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### Test plan
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commands you used and note down tests that you have written if
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Author: larryliu0820

.github/workflows/pull.yml

@@ -706,9 +706,12 @@ jobs:
         conda activate "${CONDA_ENV}"
 
         source .ci/scripts/utils.sh
-        install_executorch "--use-pt-pinned-commit"
 
+        # Run this first so that torch won't be overriden
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-mediatek-deps.sh
+        install_executorch
+        pip list
+        # debug
         PYTHON_EXECUTABLE=python bash .ci/scripts/build-mediatek-sdk.sh
         PYTHON_EXECUTABLE=python bash .ci/scripts/test_model.sh "mv3" "buck2" "mediatek"
         # placeholder for mediatek to add more tests