private Flux<UserRelationship> queryRelationships(
            @Nullable Set<Long> ownerIds,
            @Nullable Set<Long> relatedUserIds,
            @Nullable Boolean isBlocked,
            @Nullable DateRange establishmentDateRange,
            @Nullable Integer page,
            @Nullable Integer size) {
        return userRelationshipRepository.findRelationships(ownerIds,
                relatedUserIds,
                isBlocked,
                establishmentDateRange,
                page,
                size);
    }
@return true if the relationship existed and has been deleted;
        <p>
        false if the relationship does not exist, or still exists and has been deleted from a
        relationship group.
turms-service/src/main/java/im/turms/service/domain/user/service/UserRelationshipService.java