hide warnings from gcc version override

Signed-off-by: Nigel Jones <[email protected]>

.github/workflows/unix.yml

@@ -215,7 +215,7 @@ jobs:
       - name: Patch GCC 
         # Revert GCC from 13.3.0 to 13.2.0. See https://github.com/open-quantum-safe/liboqs/issues/1804
         # Note - stderr from install is hidden to avoid adding build error annotations when installing from ruby formula
-        run: env HOMEBREW_NO_AUTO_UPDATE=1 brew uninstall --ignore-dependencies gcc@13 && wget https://raw.githubusercontent.com/Homebrew/homebrew-core/eb6dd225d093b66054e18e07d56509cf670793b1/Formula/g/gcc%4013.rb && env HOMEBREW_NO_AUTO_UPDATE=1 brew install --ignore-dependencies [email protected] 2>&1
+        run: env HOMEBREW_NO_AUTO_UPDATE=1 brew uninstall --ignore-dependencies gcc@13 && wget https://raw.githubusercontent.com/Homebrew/homebrew-core/eb6dd225d093b66054e18e07d56509cf670793b1/Formula/g/gcc%4013.rb && env HOMEBREW_NO_AUTO_UPDATE=1 brew install --ignore-dependencies [email protected] 2>&1|grep -v 'Error: Failed to load cask'
       - name: Get system information
         run: sysctl -a | grep machdep.cpu
       - name: Configure