title: Spring Keycloak jwt map Create At Date to Token
body: <p>I am developing a rest api with spring boot and I use Keycloak with openid connect ( Oauth2) for my auth flow.
  I want to create an endpoint for querying data. If the "from" timestmap is not set ( I declared it as optional) I want to use the data since account creation. In order to make a request to the keycloak admin rest api I would prefer to get this information from the token. 
  I've had a look at the different built in scopes ( microprofile-jwt etc. ) but I can't find the specific mapper.Also google couldn't help me out.</p>
  
  <p>I use Keycloak 6.0.1.
  Is it possible witht his version? Or will I have to spent a rest call to the admin api?</p>
  
  <p>I know I can create a timestamp in my attributes and map it in the token but if possible I want to use to auto created by keycloak</p>