result = AddUserToGroup.call group: @group, user: current_user
puts result.user_group
=> #<UserGroup id: 1, user_id: 1, group_id: 1>
puts result.message
=> You have successfully joined the Example group!
result = AddUserToGroup.call group: @group, user: current_user
puts result.user_group
=> #<UserGroup id: 1, user_id: 1, group_id: 1>
puts result.message
=> You have successfully joined the Example group!