private String signedToken(String privateKey) throws Exception {
        JwtBuilder jwts = Jwts.builder().setSubject("france frichot")
                .signWith(SignatureAlgorithm.RS256, PemUtils.decodePrivateKey(privateKey));
        return jwts.compact();
   }
@author Marc Savy {@literal <msavy@redhat.com>}
plugins/jwt-policy/src/test/java/io/apiman/plugins/jwt/JWTPolicyTest.java