Remove traces of V3 personality extension from api samples

Removes occurences of the personality extension from the V3 API
samples as the extension has been removed. Cleanup of consistency
of image and flavor ref examples for the api samples.

DocImpact

Partially implements blueprint v3-api-remove-extensions

Change-Id: I43a34097904d3d7e280039c3d5d76479a49e92d0
Merge "Remove traces of V3 personality extension from api samples"