Changing permalink structure results in failure to save draft posts

[omikheev]

Steps to reproduce:

1. On a fresh install change Permalink structure from plain to Month and date
2. Create new Blog Post
3. Click Save draft

EXPECTED: draft is saved
OBSERVED: Error "Updating failed. The response is not a valid JSON response."

Root cause:

POST ​https://abc.com/wp-json/wp/v2/posts/93?_locale=user
HTTP/1.1 404 Not Found
Date: Sat, 23 Sep 2023 21:05:16 GMT
Server: Apache/2.4.57 (CentOS Stream) OpenSSL/3.0.7
Content-Length: 196
Keep-Alive: timeout=5, max=100
Connection: Keep-Alive
Content-Type: text/html; charset=iso-8859-1