Print what is being executed

Author: k0kubun

bin/update-default-gem.sh

@@ -25,6 +25,7 @@ function log() {
 
 # Run a given command. If it fails, notify Slack and exits abnormally.
 function run() {
+  echo "$ $@"
   if ! "$@"; then
     "${this_repo}/bin/notify-slack-failed-gem-update.rb" "$log_path" >> "$log_path" 2>&1
     log "Failed: $@"