Adding windows wheel builds (#7540)

.github/workflows/build-wheels-windows.yml

+name: Build Windows Wheels
+
+on:
+  pull_request:
+  push:
+    branches:
+      - nightly
+      - main
+      - release/*
+    tags:
+        # NOTE: Binary build pipelines should only get triggered on release candidate builds
+        # Release candidate tags look like: v1.11.0-rc1
+        - v[0-9]+.[0-9]+.[0-9]+-rc[0-9]+
+  workflow_dispatch:
+
+jobs:
+  generate-matrix:
+    uses: pytorch/test-infra/.github/workflows/generate_binary_build_matrix.yml@main
+    with:
+      package-type: wheel
+      os: windows
+      test-infra-repository: pytorch/test-infra
+      test-infra-ref: main
+  build:
+    needs: generate-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - repository: pytorch/vision
+            pre-script: packaging/pre_build_script.sh
+            env-script: packaging/windows/internal/vc_env_helper.bat
+            post-script: "python packaging/wheel/relocate.py"
+            smoke-test-script: test/smoke_test.py
+            package-name: torchvision
+    name: ${{ matrix.repository }}
+    uses: pytorch/test-infra/.github/workflows/build_wheels_windows.yml@main
+    with:
+      repository: ${{ matrix.repository }}
+      ref: ""
+      test-infra-repository: pytorch/test-infra
+      test-infra-ref: main
+      build-matrix: ${{ needs.generate-matrix.outputs.matrix }}
+      pre-script: ${{ matrix.pre-script }}
+      env-script: ${{ matrix.env-script }}
+      post-script: ${{ matrix.post-script }}
+      package-name: ${{ matrix.package-name }}
+      smoke-test-script: ${{ matrix.smoke-test-script }}
+      # Using "development" as trigger event so these binaries are not uploaded
+      # to official channels yet
+      trigger-event: development
+    secrets:
+      AWS_PYTORCH_UPLOADER_ACCESS_KEY_ID: ${{ secrets.AWS_PYTORCH_UPLOADER_ACCESS_KEY_ID }}
+      AWS_PYTORCH_UPLOADER_SECRET_ACCESS_KEY: ${{ secrets.AWS_PYTORCH_UPLOADER_SECRET_ACCESS_KEY }}

packaging/pre_build_script.sh

 #!/bin/bash
-if [[ "$(uname)" == Darwin || "$OSTYPE" == "msys" ]]; then
+if [[ "$(uname)" == Darwin ]]; then
   # Uninstall Conflicting jpeg brew formulae
   jpeg_packages=$(brew list | grep jpeg)
   echo "Existing Jpeg-related Brew libraries"
@@ -8,10 +8,13 @@ if [[ "$(uname)" == Darwin || "$OSTYPE" == "msys" ]]; then
     brew uninstall --ignore-dependencies --force $pkg || true
   done
 
+  conda install -yq wget
+fi
+
+if [[ "$(uname)" == Darwin || "$OSTYPE" == "msys" ]]; then
   # Install libpng from Anaconda (defaults)
   conda install ${CONDA_CHANNEL_FLAGS} libpng "jpeg<=9b" -y
   conda install -yq ffmpeg=4.2 -c pytorch
-  conda install -yq wget
 else
   # Install native CentOS libJPEG, freetype and GnuTLS
   yum install -y libjpeg-turbo-devel freetype gnutls