docs: public HalFormsDocument<T> andEmbedded(HalLinkRelation key, Object value) {
  
  		Assert.notNull(key, "Embedded key must not be null!");
  		Assert.notNull(value, "Embedded value must not be null!");
  
  		Map<HalLinkRelation, Object> embedded = new HashMap<>(this.embedded);
  		embedded.put(key, value);
  
  		return new HalFormsDocument<>(resource, resources, embedded, pageMetadata, links, templates);
  	}