CI: Skip homebrew update/cleanup on macOS (#790)

The auto cleanup step that runs after `brew install` can can often add a
few minutes to each macOS CI run.

diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 1469033bb79e7107986cd30df064213f891fd0b1..c222a199cfa25729f558508bf2b967d0fac50480 100644 (file)
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -111,7 +111,9 @@ jobs:
               sudo apt install -y clang-${{ matrix.config.version }} g++-multilib
             fi
           elif [ "${{ runner.os }}" = "macOS" ]; then
-            brew install ninja
+            HOMEBREW_NO_AUTO_UPDATE=1 HOMEBREW_NO_INSTALL_CLEANUP=1 \
+              brew install ninja
+
             if [ "${{ matrix.config.compiler }}" = "gcc" ]; then
               brew install gcc@${{ matrix.config.version }}
               echo "CC=gcc-${{ matrix.config.version }}" >> $GITHUB_ENV