[Github] Remove install-ninja/setup-windows

This patch backports a couple of patches that Tom and I submitted
recently to drop the usages of these actions. This allows us to delete
the usages in llvm/actions while keeping CI running in the release
branch.

Author: boomanaiden154

.github/workflows/hlsl-test-all.yaml

@@ -52,11 +52,6 @@ jobs:
           repository: llvm/offload-golden-images
           ref: main
           path: golden-images
-      - name: Setup Windows
-        if: runner.os == 'Windows'
-        uses: llvm/actions/setup-windows@main
-        with:
-          arch: amd64
       - name: Build DXC
         run: |
             cd DXC

.github/workflows/libclang-abi-tests.yml

@@ -101,8 +101,6 @@ jobs:
             ref: ${{ github.sha }}
             repo: ${{ github.repository }}
     steps:
-      - name: Install Ninja
-        uses: llvm/actions/install-ninja@42d80571b13f4599bbefbc7189728b64723c7f78 # main
       - name: Download source code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
         with:

.github/workflows/premerge.yaml

@@ -146,7 +146,8 @@ jobs:
         with:
           max-size: "2000M"
       - name: Install Ninja
-        uses: llvm/actions/install-ninja@main
+        run: |
+          brew install ninja
       - name: Build and Test
         run: |
           source <(git diff --name-only HEAD~1...HEAD | python3 .ci/compute_projects.py)

.github/workflows/release-binaries.yml

@@ -199,15 +199,6 @@ jobs:
       with:
         ref: ${{ needs.prepare.outputs.ref }}
 
-    - name: Install Ninja
-      uses: llvm/actions/install-ninja@a1ea791b03c8e61f53a0e66f2f73db283aa0f01e # main
-
-    - name: Setup Windows
-      if: startsWith(runner.os, 'Windows')
-      uses: llvm/actions/setup-windows@main
-      with:
-        arch: amd64
-
     - name: Set Build Prefix
       id: setup-stage
       shell: bash