Clarify OAuth2 Client Configuration Documentation

docs/configuration/oauth2-client.md

@@ -2,7 +2,8 @@
 
 If an agent is supposed to authenticate at an endpoint via OAuth2 one must register one or more
 clients.
-The registration's name has to be set in [HttpClientConfig](../types/HttpClientConfig).
+Then the registration may be referenced by its `registrationId`
+in [HttpClientConfig](../types/HttpClientConfig).
 
 See [Spring Security](https://docs.spring.io/spring-security/reference/servlet/oauth2/client/core.html#oauth2Client-client-registration)
 for more details on how to configure OAuth2 clients.
@@ -21,13 +22,3 @@ spring.security.oauth2.client:
     keycloak:
       issuer-uri: http://localhost:8080/realms/fts
 ```
-
-## Fields
-
-### `registration` _(list)_
-
-* Key-value map of `$REGISTRATION_NAME` to ClientRegistration
-
-
-* ### `provider` _(list)_
-  Key-value map of `$PROVIDER_ID` to ProviderDetails.