Mismatch between numberOfPosts attribute and size of Posts attribute can cause posts to disappear in the admin

[mogmarsh]

Description of the bug

If the numberOfPosts attribute is set to 3 but the posts attribute is [123,456,789,null] (4 slots), a post will get backfilled into the 4th slot, but not show up in the editor. It may show up on the front end in a different spot. This bug does not seem to affect the front end.

Steps To Reproduce

add a query block, manually change the attributes so there is a mismatch (there may be a way to do it through the GUI, but I don't know if there is).
Add an additional query block
Watch the requests to the rest API, you will see 4 posts are requested, but the 4th one will never appear in the editor.
Fix the mismatch, you should see the missing post.

Additional Information

No response