[docs] delete duplicated image_status_transition.png
[docs] delete duplicated image_status_transition.png

This patch deletes image_status_transition.png from
incorrect location (source/images_src/).

Change-Id: I6c679650d411a43047a06bdc4eb29863a86a37f1
Closes-Bug: #1516032

klmitch/glance,rajalokan/glance,dims/glance,openstack/glance,klmitch/glance,openstack/glance,stevelle/glance,dims/glance,rajalokan/glance,stevelle/glance,openstack/glance