Changes to Generate Blog Posts

added the new required request property posts/items/title

the posts/items request property type changed from string to object

added the new optional request property posts/items/summary

added the new optional request property posts/items/topic_type

the request property audience became nullable

the request property category_profile became nullable

the request property count became nullable

the request property description became nullable

the request property language became nullable

the request property max_words became nullable

the request property min_words became nullable

the request property tone became nullable