[llvm] workflows/release-binaries: Always pull composite actions from main branch (PR #100805)

[Tom Stellard via llvm-commits]

================
@@ -148,6 +148,20 @@ jobs:
     if: github.repository == 'llvm/llvm-project'
     runs-on: ${{ inputs.runs-on }}
     steps:
+
+    - name: Checkout Actions
+      uses: actions/checkout at v4
+      with:
+        ref: ${{ (github.event_name == 'pull_request' && github.sha) || 'main' }}
+        sparse-checkout: |
+          .github/workflows/
+        sparse-checkout-cone-mode: false
+        path: workflows
+
+    - name: Setup Stage
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tstellar wrote:

I was wrong, the checkout does overwrite this.  See https://github.com/llvm/llvm-project/pull/100845.

https://github.com/llvm/llvm-project/pull/100805