fix: also fix the versions of torch-sparse to avoid independency inst…

…all error during CI testing;

.github/workflows/testing_ci.yml

@@ -58,7 +58,7 @@ jobs:
             - name: Install other dependencies
               run: |
                   pip install pypots
-                  pip install torch-geometric==2.3.1 torch-scatter==2.1.1 torch-sparse -f "https://data.pyg.org/whl/torch-${{ matrix.torch-version }}+cpu.html"
+                  pip install torch-geometric==2.3.1 torch-scatter==2.1.1 torch-sparse==0.6.17 -f "https://data.pyg.org/whl/torch-${{ matrix.torch-version }}+cpu.html"
                   pip install -e ".[dev]"
 
             - name: Fetch the test environment details