[Security] fixed pre/post authentication checks

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8510, #9622
| License       | MIT
| Doc PR        | N/A

After further investigation of #8510, I found that all checks in the `checkPreAuth` actually belongs to `checkPostAuth` and the same goes for checks in `CheckPostAuth` (I checked the original source from Spring and indeed, that's how it is implemented there: see https://github.com/spring-projects/spring-security/blob/master/core/src/main/java/org/springframework/security/authentication/dao/AbstractUserDetailsAuthenticationProvider.java#L305
).

So, this PR fixes that issue. I think that we can do this change safely in 2.3 as the error message is the same for all causes by default (`$hideUserNotFoundExceptions` is `true` by default in `UserAuthenticationProvider`).

The only "real" change is whether the authentication is checked or not.