Fix torch version to make torchrec CI tests work (#3211)

Summary:

Fix torch version to make torchrec CI tests work

Rollback Plan:

Differential Revision: D78564722

Author: nipung90

.github/workflows/unittest_ci_cpu.yml

@@ -61,7 +61,7 @@ jobs:
         python --version
         conda run -n build_binary python --version
         conda run -n build_binary \
-          pip install torch --index-url https://download.pytorch.org/whl/nightly/cpu
+          pip install torch==2.9.0.dev20250716+cpu --index-url https://download.pytorch.org/whl/nightly/cpu
         conda run -n build_binary \
           python -c "import torch"
         echo "torch succeeded"