.github/scripts/macOS/prepare.sh: suppres brew out

suppress `brew list` output

It is used just to check if a package is installed and the output is
print is output to stdout. To stderr is print that it if the package is
not installed.

.github/scripts/macOS/prepare.sh

@@ -68,7 +68,7 @@ set -- \
 # shellcheck disable=SC2034
 for n in $(seq $#); do
         # if not installed, add on the back of positional parameters
-        if ! brew list "$1" 2>/dev/null; then
+        if ! brew list "$1" >/dev/null 2>&1; then
                 set -- "$@" "$1"
         fi
         shift # remove from the front

.github/workflows/ccpp.yml

@@ -215,7 +215,7 @@ jobs:
       id: upload-release
       if: (github.repository == 'CESNET/UltraGrid' && github.ref == 'refs/heads/master') || startsWith(github.ref, 'refs/tags/')
       run: |
-        brew list jq 2>/dev/null || brew install jq
+        brew list jq >/dev/null 2>&1 || brew install jq
         .github/scripts/replace-asset.sh $TAG UltraGrid-$VERSION.dmg application/x-apple-diskimage macOS%20$(uname -m)%20build
     - name: Upload Build
       if: steps.upload-release.conclusion == 'skipped'