code: public BUILDER setStorageRuntime() {
          removeFlag(AttributeAccess.Flag.STORAGE_CONFIGURATION);
          return addFlag(AttributeAccess.Flag.STORAGE_RUNTIME);
      }
docs: Adds the {@link AttributeAccess.Flag#STORAGE_RUNTIME} flag and removes any conflicting flag.
  
  @return a builder that can be used to continue building the attribute definition