Fix AuthnRequestConverter Sample Typos

Closes gh-10364

Author: jzheaux

docs/manual/src/docs/asciidoc/_includes/servlet/saml2/saml2-login.adoc

@@ -739,7 +739,7 @@ But, if you do need something from the request, then you can use create a custom
 ----
 @Component
 public class AuthnRequestConverter implements
-        Converter<MySaml2AuthenticationRequestContext, AuthnRequest> {
+        Converter<Saml2AuthenticationRequestContext, AuthnRequest> {
 
 	private final AuthnRequestBuilder authnRequestBuilder;
 	private final IssuerBuilder issuerBuilder;