message: Fix incremental build script for mac
  mktemp on mac does not support `--tmpdir`
  Closes:
  Approved by: ankushagarwal
diff: @@ -14,7 +14,7 @@ fi
  rm -f libra-node-from-docker
  -DOCKERFILE="$(mktemp --tmpdir Dockerfile.XXXXXX)"
  +DOCKERFILE="$(mktemp -t Dockerfile.XXXXXX)"
  awk '/FROM.*AS builder/ { exit } { print } ' $DIR/../validator/validator.Dockerfile > "$DOCKERFILE"
  docker build -f "$DOCKERFILE" $DIR/../.. --tag libra-node-builder $PROXY
  @@ -30,6 +30,6 @@ fi
  docker exec -i -t libra-node-builder-container bash -c 'source /root/.cargo/env; cargo build --release -p libra-node --target-dir /target && /bin/cp /target/release/libra-node target/libra-node-builder/'
  -DOCKERFILE="$(mktemp --tmpdir Dockerfile.XXXXXX)"
  +DOCKERFILE="$(mktemp -t Dockerfile.XXXXXX)"
  awk '/^FROM.*AS prod/ { from=1 } /^COPY/ { sub(/--from=.*release/, "target/libra-node-builder", $0) } { if (from) print }' $DIR/../validator/validator.Dockerfile > "$DOCKERFILE"
  docker build -f "$DOCKERFILE" $DIR/../.. --tag libra_e2e --build-arg GIT_REV="$(git rev-parse HEAD)" --build-arg GIT_UPSTREAM="$(git merge-base HEAD origin/master)" --build-arg BUILD_DATE="$(date -u +'%Y-%m-%dT%H:%M:%SZ')" $PROXY
  