change default Docker Quickstart Terminal for Mac

For some reason I'd change Docker Quickstart Terminal to Mac default Terminal instead of iTem. But it failed at first tries, even by uninstalling docker from Mac system.

Searching such config file by name "default_terminal", there is a text file to record this option. Removing this file and relaunch docker, or, just edit it directly will close this issue.

 ⓑ maxwu  16:32  ~  devel  circleci-stat   master  sudo find / -name default_terminal
Password:
find: /dev/fd/3: Not a directory
find: /dev/fd/4: Not a directory
/Users/maxwu/Library/Application Support/DockerToolbox/default_terminal
 ⓑ maxwu  16:34  ~  devel  circleci-stat   master  vim /Users/maxwu/Library/Application\ Support/DockerToolbox/default_terminal
 ⓑ maxwu  16:35  ~  devel  circleci-stat   master 