message: [gha] be more explicit with breaking tag check
  Closes:
  Approved by: andll
diff: @@ -57,10 +57,11 @@ jobs:
  set +e
  commit_message=$(git log --pretty=oneline $MASTER_GIT_REV..$LIBRA_GIT_REV)
  echo $commit_message | grep '\[breaking\]'
  + ret=$?
  if ${{ secrets.KILL_SWITCH_LAND_BLOCKING_COMPAT }}; then
  echo "Compat killswitch activated! Will run land_blocking suite"
  echo "::set-env name=TEST_COMPAT::0"
  - elif [ $? -eq 0 ]; then
  + elif [ $ret -eq 0 ]; then
  echo "Breaking change detected! Will run land_blocking suite"
  echo "::set-env name=TEST_COMPAT::0"
  else
  