GUACAMOLE-1364: Correct naming of SAML auth field and translation.

extensions/guacamole-auth-sso/modules/guacamole-auth-sso-saml/src/main/java/org/apache/guacamole/auth/saml/AuthenticationProviderService.java

@@ -110,7 +110,8 @@ public class AuthenticationProviderService {
         URI authUri = saml.createRequest();
         throw new GuacamoleInsufficientCredentialsException("Redirecting to SAML IdP.",
                 new CredentialsInfo(Arrays.asList(new Field[] {
-                    new RedirectField("samlRedirect", authUri, new TranslatableMessage("LOGIN.INFO_IDP_REDIRECT_PENDING"))
+                    new RedirectField(AUTH_SESSION_QUERY_PARAM, authUri,
+                            new TranslatableMessage("LOGIN.INFO_IDP_REDIRECT_PENDING"))
                 }))
         );