ci: speed up Python test (#3776)

Reduce installation time from 2.5 min to 1.5 min.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Refactor**
- Enhanced Python environment setup and package installation processes
to improve performance and compatibility.
- **Chores**
- Updated package management commands to ensure the latest versions of
necessary libraries are used.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Signed-off-by: Jinzhe Zeng <[email protected]>

.github/workflows/test_python.yml

@@ -23,23 +23,16 @@ jobs:
     - uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python }}
-    - uses: mpi4py/setup-mpi@v1
-      with:
-        mpi: openmpi
     - run: python -m pip install -U uv
-    - run: uv pip install --system -e .[cpu,test,torch]
+    - run: uv pip install --system --only-binary=horovod -e .[cpu,test,torch] horovod[tensorflow-cpu] mpi4py mpich
       env:
         # Please note that uv has some issues with finding
         # existing TensorFlow package. Currently, it uses
         # TensorFlow in the build dependency, but if it
         # changes, setting `TENSORFLOW_ROOT`.
-        TENSORFLOW_VERSION: ${{ matrix.tf }}
+        TENSORFLOW_VERSION: ${{ matrix.python == '3.8' && '2.13.1' || '2.16.1' }}
         DP_BUILD_TESTING: 1
-    - run: uv pip install --system --no-build-isolation horovod mpi4py
-      env:
-        HOROVOD_WITH_TENSORFLOW: 1
-        HOROVOD_WITHOUT_PYTORCH: 1
-        HOROVOD_WITHOUT_GLOO: 1
+        UV_EXTRA_INDEX_URL: "https://pypi.anaconda.org/njzjz/simple https://pypi.anaconda.org/mpi4py/simple"
     - run: dp --version
     - name: Get durations from cache
       uses: actions/cache@v4