code: @NotNull
      @ObjectiveCName("editGroupAboutWithGid:withAbout:")
      public Promise<Void> editGroupAbout(int gid, String about) {
          return modules.getGroupsModule().editAbout(gid, about);
      }
docs: Edit group's about
  
  @param gid   group's id
  @param about new group about
  @return Promise for void