Test Homebrew Formula (macOS) fails with `Error: cmake is already installed from local/pinned!`

[cruessler]

Currently, “Test Homebrew Formula (macOS)” fails with the following error:

Run brew install --head --build-from-source gitui
# rest of the output omitted, see bottom for full log
==> Installing dependencies for gitui: cmake, libgit2, llvm@20 and rust
Error: cmake is already installed from local/pinned!
Please `brew uninstall cmake` first."

This seems related to
actions/runner-images#12912.

GH Actions log for `brew install --head --build-from-source gitui`

Run brew install --head --build-from-source gitui
==> Fetching downloads for: gitui
==> Downloading https://raw.githubusercontent.com/Homebrew/homebrew-core/3f0d1470ab9dfd13e5337242bf8f94b90397dbea/Formula/g/gitui.rb
==> Fetching dependencies for gitui: cmake, libgit2, llvm@20 and rust
==> Downloading https://ghcr.io/v2/homebrew/core/cmake/manifests/4.1.1
==> Fetching cmake
==> Downloading https://ghcr.io/v2/homebrew/core/cmake/blobs/sha256:15af42c171e6914039f7188154145d20484a565bb43b308be9efbdcc893884af
==> Downloading https://ghcr.io/v2/homebrew/core/libgit2/manifests/1.9.1
==> Fetching libgit2
==> Downloading https://ghcr.io/v2/homebrew/core/libgit2/blobs/sha256:3be60ae5bc7e68b788b021eaf00927f595c28bfed352cd5bf8c212494392dfb8
==> Downloading https://ghcr.io/v2/homebrew/core/llvm/20/manifests/20.1.8
==> Fetching llvm@20
==> Downloading https://ghcr.io/v2/homebrew/core/llvm/20/blobs/sha256:a8bbf20183038cbf5c5955bcb7ad88f86b9c52b8f4fa2153300726275277769f
==> Downloading https://ghcr.io/v2/homebrew/core/rust/manifests/1.89.0_2
==> Fetching rust
==> Downloading https://ghcr.io/v2/homebrew/core/rust/blobs/sha256:8988880d5519ccbad2f8d4195e6b10b573b23644193ff7f247dff00814ef3b7b
==> Fetching gitui
==> Cloning https://github.com/gitui-org/gitui.git
Cloning into '/Users/runner/Library/Caches/Homebrew/gitui--git'...
==> Checking out branch master
Already on 'master'
Your branch is up to date with 'origin/master'.
==> Installing dependencies for gitui: cmake, libgit2, llvm@20 and rust
Error: cmake is already installed from local/pinned!
Please `brew uninstall cmake` first."