Fix incorrect reference to `Ember` in updated example code
Fix incorrect reference to `Ember` in updated example code

Commit 9f5d4022ca0f76310fd570c3fe4f15eb2722d254 changed a code
snippet, but left a reference to the previous code in place. This
change updates the text so that it reflects the change in the code.

skaterdav85/guides,tleskin/guides,skaterdav85/guides,tleskin/guides,skaterdav85/guides,skaterdav85/guides,tleskin/guides