public Mono<Boolean> checkIfUserExists(@NotNull Long userId, boolean queryDeletedRecords) {
        try {
            Validator.notNull(userId, "userId");
        } catch (ResponseException e) {
            return Mono.error(e);
        }
        return userRepository.checkIfUserExists(userId, queryDeletedRecords);
    }
@return Possible codes: {@link ResponseStatusCode#OK}
        {@link ResponseStatusCode#NOT_FRIEND_TO_QUERY_USER_PROFILE}
        {@link ResponseStatusCode#BLOCKED_USER_TO_QUERY_USER_PROFILE}
        {@link ResponseStatusCode#SERVER_INTERNAL_ERROR}
        {@link ResponseStatusCode#RESOURCE_NOT_FOUND}
turms-service/src/main/java/im/turms/service/domain/user/service/UserService.java