Admin throws error "Cannot find the class related to [Entrypoint/RESOURCE_NAME]" if POST operation is removed from ApiResource

[enridelg]

API Platform version(s) affected: 4.0.6

Description
When I remove the POST operation from an ApiResource, the Admin UI throws the following error:
Cannot find the class related to https://localhost/api/docs.jsonld#Entrypoint/[RESOURCE_NAME]
Enabling Hydra prefixes in the API Platform config (which is disabled by default in v4) resolves the issue with the same resource operations.

How to reproduce
In a fresh install of API Platform (v4.x), modify the Greeting resource to only include GET and GET Collection operations:

#[ApiResource(operations: [new Get(), new GetCollection()])]

Expected behavior
The Admin UI should work even if the POST operation is removed from the resource, and without requiring Hydra to be explicitly enabled.