[llvm] [premerge] Route macOS build through a monolithic script to enable Job Summary (PR #211565)

[Arseniy Obolenskiy via llvm-commits]

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@@ -278,9 +278,9 @@ jobs:
         with:
           persist-credentials: false
           fetch-depth: 2
-      - name: Install Ninja, CMake, and sccache
+      - name: Install Ninja, CMake, Python, and sccache
         run: |
-          brew install ninja cmake
+          brew install ninja cmake python
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aobolensk wrote:

Switched back 

https://github.com/llvm/llvm-project/pull/211565