private static String getContent(final Response response) {
        String msg = "";
        if (response != null) {
            try {
                msg = response.readEntity(String.class);
            } catch (final Exception e) {
                // Just swallow it in case there is no content
            }
        }
        return msg;
    }
Allows you do define client credentials that differ from those in {@link OpenIdConfiguration}
stroom-security/stroom-security-common-impl/src/main/java/stroom/security/common/impl/OpenIdTokenRequestHelper.java