Tested by trigger `grpc/core/master/linux/psm-csm-python` job manually:
- [x] [grpc/core/master/linux/psm-csm-python](https://source.cloud.google.com/results/invocations/31cb5a6e-ed44-4dd7-a383-14bf0a5907b0)
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Closes#35644
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35644 from XuanWang-Amos:xds_add_psm_csm_python_test e2d1a62052
PiperOrigin-RevId: 602827145
Xuan Wang