New utility method to access the `access-token` string

src/main/java/org/gcube/portal/oidc/lr62/JWTTokenUtil.java

@@ -18,6 +18,10 @@ public class JWTTokenUtil {
         return token.getRaw();
     }
 
+    public static String getAccessTokenString(JWTToken token) {
+        return token.getAccessTokenString();
+    }
+
     public static JWTToken getOIDCFromRequest(HttpServletRequest request) {
         return JWTToken.fromString((String) request.getAttribute(OIDC_TOKEN_ATTRIBUTE));
     }