Add a new team user with desired details.

In the request body:

* email is the contact email address of your new user;
* password could be an initial login password you asign to them;
* name is the display name of your new user;
* with_workspace should be set to true if you want your new user to acquire a workspace_id immediately after adding them. The default value is false, which means they won't have a workspace_id until they login for the first time.