code: Observable<ComapiResult<Void>> doAddParticipants(@NonNull final String token, @NonNull final String conversationId, @NonNull final List<Participant> participants) {
          return wrapObservable(service.addParticipants(AuthManager.addAuthPrefix(token), apiSpaceId, conversationId, participants).map(mapToComapiResult()), log, "Adding participants to " + conversationId);
      }
docs: Returns observable to add a list of participants to a conversation.
  
  @param token          Comapi access token.
  @param conversationId ID of a conversation to update.
  @param participants   New conversation participants details.
  @return Observable to add participants to a conversation.