Add a simple compatibility function for AWX 9.x.x. Before AWX 9.x.x
a "friendly_name" key was sent by default. Afterwards it was removed
from being a default key but we can still more or less determine if
the triggering event was a job from the REST-style URL.
Note: It is also technically possible to add the key back by defining
a custom notification template in AWX/Tower.
Resolves#13295.