CI: temporarily disable macOS 11 test

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

.github/workflows/ci.yml

@@ -86,10 +86,12 @@ jobs:
           brew uninstall --ignore-dependencies libx11 # https://github.com/ziglang/zig/issues/11066
           brew install xz
           sudo sh -c 'wget -c https://ziglang.org/builds/zig-macos-x86_64-0.10.0-dev.1600+af844931b.tar.xz -O - | tar -xJ --strip-components=1 -C /usr/local/bin'
-      - name: test
-        run: cd ${{ matrix.project }} && zig build test
-        env:
-          AGREE: true
+      # TODO: re-enable once we can use macos-12 reliably on GitHub actions (currently works, but
+      #       takes a very long time to acquire macos-12 runners.)
+      # - name: test
+      #   run: cd ${{ matrix.project }} && zig build test
+      #   env:
+      #     AGREE: true
       - name: x86_64-macos -> aarch64-macos
         run: cd ${{ matrix.project }} && zig build test -Dtarget=aarch64-macos.12...12-gnu
         env: