Changes to Get an article by its UUID

added the optional property wikidata_entities/anyOf[subschema #1]/additionalProperties/items/source_mentions to the response with the 200 status

the response property centroid_distance became optional for the status 200

the response property cluster_probability became optional for the status 200

response property centroid_distance list-of-types was widened by adding types null to media type application/json of response 200

response property cluster_probability list-of-types was widened by adding types null to media type application/json of response 200

added the optional property wikidata_entities to the response with the 200 status