docs: public Assertion newAssertion(final AuthenticationStatement authnStatement, final String issuer,
                                    final ZonedDateTime issuedAt, final String id) {
          val assertion = newSamlObject(Assertion.class);
  
          assertion.setID(id);
          assertion.setIssueInstant(DateTimeUtils.dateTimeOf(issuedAt));
          assertion.setIssuer(issuer);
          assertion.getAuthenticationStatements().add(authnStatement);
          return assertion;
      }