[ci] Install torch for windows release (#3932)

Author: qiao-bo

.github/workflows/release.yml

@@ -351,6 +351,7 @@ jobs:
           $env:PATH = ";C:\taichi_llvm\bin;C:\taichi_clang\bin;" + $env:PATH
           . venv\Scripts\activate.ps1
           python -c "import taichi"
+          pip install torch
           ti diagnose
           python tests/run_tests.py -vr2 -t2
         env: