title: how to get claims value from JWT token authentication
body: <p>I have set claims in JWT token in the token provider. now I want to get claim value through authentication when API is hit.</p>
  
  <p>I have checked in Principal, details, credential, authorities but I am not getting claims in any of them.</p>
  
  <pre><code>Claims claims = Jwts.claims().setSubject(authentication.getName());
      claims.put(AUTHORITIES_KEY, authorities);
      claims.put("userId", userRepo.findUserIdByUsername(authentication.getName()));
  
     return Jwts.builder()
              .setSubject(authentication.getName())
              .setClaims(claims)
              //.claim(AUTHORITIES_KEY, authorities)
              .signWith(SignatureAlgorithm.HS512, SIGNING_KEY)
              .setIssuedAt(new Date(System.currentTimeMillis()))
              .setExpiration(new Date(System.currentTimeMillis() + ACCESS_TOKEN_VALIDITY_SECONDS*1000))
              .compact();
  </code></pre>
  
  <p>I want to get "userId" claim from the authentication or any other way to get claims value from token.</p>