Post List Continuously Loads without Displaying Posts in Pattern Creation Too

Description:
When attempting to create a new pattern using the post list block on the WordPress Pattern Creation page (https://wordpress.org/patterns/new-pattern/), the block fails to display any posts and shows a perpetual loading indicator. This issue occurs during the pattern creation process and prevents users from effectively using the post list block in their custom patterns.

Steps to Reproduce:

1. Navigate to https://wordpress.org/patterns/new-pattern/ on Google Chrome.
2. Begin creating a new pattern.
3. Add a 'Post List' block to the pattern.
4. Observe the behavior of the Post List block.

Expected Result:
The Post List block should successfully load and display a list of posts.

Actual Result:
The Post List block continuously shows a loading spinner and does not display any posts.

Environment:

• WordPress Version: 6.5.2
• Browser: Google Chrome

Additional Information:

• A video demonstrating the issue is available here: Video Link
• The issue may be related to AJAX requests are completing but not fetching data on the client side.

Console/ Network Output: It is loading the API well and getting the data but just not populating on the screen.

Start at the Pattern Creation page and inspect the Post List block's client-side API response and rendering path. Reproduce the issue in Chrome and verify that the returned posts are populated in the block instead of leaving the loading spinner visible.