Default WebAuthnConfigurer#rpName to rpId

In WebAuthn L3 spec, PublicKeyCredentialEntity.name is deprecated:

> This member is deprecated because many clients do not display it,
> but it remains a required dictionary member for backwards compatibility.
> Relying Parties MAY, as a safe default, set this equal to the RP ID.

Source: https://www.w3.org/TR/webauthn-3/#dictdef-publickeycredentialentity

Signed-off-by: Daniel Garnier-Moiroux <git@garnier.wf>

docs/modules/ROOT/pages/servlet/authentication/passkeys.adoc

@@ -64,7 +64,6 @@ SecurityFilterChain filterChain(HttpSecurity http) {
 		// ...
 		.formLogin(withDefaults())
 		.webAuthn((webAuthn) -> webAuthn
-			.rpName("Spring Security Relying Party")
 			.rpId("example.com")
 			.allowedOrigins("https://example.com")
 		);
@@ -91,7 +90,6 @@ Kotlin::
 open fun filterChain(http: HttpSecurity): SecurityFilterChain {
 	http {
 		webAuthn {
-			rpName = "Spring Security Relying Party"
 			rpId = "example.com"
 			allowedOrigins = setOf("https://example.com")
 		}