message: fix: clean self-runner sapce when disk space is less than threshold
diff: #!/bin/bash
  set -u
  is_self_runner=`echo $RUNNER_LABEL | awk -F '-' '{print $1}'`
  +clean_threshold=40000
  +available_space=`df -m "$GITHUB_WORKSPACE" | tail -1 | awk '{print $4}'`
  if [[ $is_self_runner == "self" ]];then
  CARGO_TARGET_DIR=$GITHUB_WORKSPACE/../target
  + #clean space when disk full
  + if [[ $available_space -lt $clean_threshold ]]; then
  + echo "Run clean command"
  + cargo clean --target-dir "${CARGO_TARGET_DIR}" || true
  + fi
  fi
  CARGO_TARGET_DIR=${CARGO_TARGET_DIR:-"$GITHUB_WORKSPACE/target"}
  EXIT_CODE=0
  