code: public static List<RequiresDirective>
              requiresIn(Iterable<? extends Directive> directives) {
          return listFilter(directives, DirectiveKind.REQUIRES, RequiresDirective.class);
      }
docs: Returns a list of {@code requires} directives in {@code directives}.
  @return a list of {@code requires} directives in {@code directives}
  @param directives the directives to filter
  @since 9
  @spec JPMS