Commit missed of overriding WebClient in ReactiveOidcIdTokenDecoderFactory

[JohnNiang]

Describe the bug
Overriding WebClient in ReactiveOidcIdTokenDecoderFactory was implemented in one part of #14357 that had two commits. But at last, only one commit got merged.

In #13301, the commit only containing author info was merged.

To Reproduce

See #14357 (comment) for more.

Expected behavior

The commit should be merged as well.

[jzheaux]

Hi, @JohnNiang, thanks for double-checking. The commit was not missed. It was reverted due to #14178 (comment).

The main concern is that it would matter for only some client registrations, causing possible confusion as to the setter's impact. You can follow that comment to see an example of how to customize WebClient.