code: public int delete(CMASpaceMembership membership) {
      final String id = getResourceIdOrThrow(membership, "membership");
      final String spaceId = getSpaceIdOrThrow(membership, "membership");
  
      final CMASystem sys = membership.getSystem();
      membership.setSystem(null);
  
      try {
        final Response<Void> response = service.delete(spaceId, id).blockingFirst();
        return response.code();
      } finally {
        membership.setSystem(sys);
      }
    }
docs: Delete the given membership instance.
  <p>
  Please make sure that the instance provided is fetched from Contentful. Otherwise you will
  get an exception thrown.
  
  @param membership the membership fetched from Contentful, updated by caller, to be deleted.
  @return the code of the response (204 means success).
  @throws IllegalArgumentException if space id is null.
  @throws IllegalArgumentException if membership id is null.