Disable auto-update of PyTorch version until CI script stabilizes (#1456)

Instead of letting the auto-update script either fail because of script
errors or letting it commit bad versions, this patch makes the update
process manual, for now.  Once the script stabilizes, I will its
re-enable periodic execution.

.github/workflows/RollPyTorch.yml

@@ -1,8 +1,6 @@
 name: Roll PyTorch
 
 on:
-  schedule:
-    - cron: '0 12 * * *'
   workflow_dispatch:
 
 jobs:

.github/workflows/buildAndTest.yml

@@ -61,7 +61,7 @@ jobs:
       if: ${{ matrix.os-arch == 'ubuntu-x86_64' }}
       run: |
         cd $GITHUB_WORKSPACE
-        TM_PACKAGES="${{ matrix.llvm-build }}" TM_USE_PYTORCH_BINARY="${{ matrix.torch-binary }}" ./build_tools/python_deploy/build_linux_packages.sh
+        TORCH_MLIR_SRC_PYTORCH_BRANCH="$(cat pytorch-version.txt)" TM_PACKAGES="${{ matrix.llvm-build }}" TM_USE_PYTORCH_BINARY="${{ matrix.torch-binary }}" ./build_tools/python_deploy/build_linux_packages.sh
     - name: Configure os-arch='macos-arm64' llvm-build='in-tree' torch-binary='${{ matrix.torch-binary }}'
       # cross compile, can't test arm64
       if: ${{ matrix.os-arch == 'macos-arm64' && matrix.llvm-build == 'in-tree' }}

build_tools/build_libtorch.sh

@@ -58,7 +58,8 @@ checkout_pytorch() {
     git reset --hard FETCH_HEAD
   else
     cd "${PYTORCH_ROOT}"
-    git reset --hard HEAD
+    git fetch --depth=1 origin "${TORCH_MLIR_SRC_PYTORCH_BRANCH}"
+    git reset --hard FETCH_HEAD
   fi
   git clean -df
   git submodule update --init --depth 1 --recursive

build_tools/python_deploy/build_linux_packages.sh

@@ -60,9 +60,9 @@ PKG_VER_FILE="${repo_root}"/torch_mlir_package_version ; [ -f "$PKG_VER_FILE" ]
 TORCH_MLIR_PYTHON_PACKAGE_VERSION="${TORCH_MLIR_PYTHON_PACKAGE_VERSION:-0.0.1}"
 echo "Setting torch-mlir Python Package version to: ${TORCH_MLIR_PYTHON_PACKAGE_VERSION}"
 
-TORCH_MLIR_SRC_PYTORCH_REPO="${TORCH_MLIR_SRC_PYTORCH_REPO:-pytorch/pytorch}"
+export TORCH_MLIR_SRC_PYTORCH_REPO="${TORCH_MLIR_SRC_PYTORCH_REPO:-pytorch/pytorch}"
 echo "Setting torch-mlir PyTorch Repo for source builds to: ${TORCH_MLIR_SRC_PYTORCH_REPO}"
-TORCH_MLIR_SRC_PYTORCH_BRANCH="${TORCH_MLIR_SRC_PYTORCH_BRANCH:-master}"
+export TORCH_MLIR_SRC_PYTORCH_BRANCH="${TORCH_MLIR_SRC_PYTORCH_BRANCH:-master}"
 echo "Setting torch-mlir PyTorch version for source builds to: ${TORCH_MLIR_SRC_PYTORCH_BRANCH}"
 
 function run_on_host() {