[BUG] TAnomaly does not count unique destination IPs correctly

[frikilax]

Describe the bug
the tanomaly filter does not count unique destination IPs for a specific source IP: the counter does not look for already counted destinations, introducing (many) duplicates in results.

Plateform (please complete the following information):

• all

To Reproduce
Steps to reproduce the behavior:

1. Start a tanomaly filter
2. Send 200+ uniform data (random ip src/dst, random port, tcp proto)
3. Send 100+ data with same IP src, but same IP dst and random port (tcp proto)
4. Wait for filter to trigger and generate alert
5. Look alert
6. alert should have a tcp_nb_host equal to the tcp_nb_port, even though there is only a single destination IP

Expected behavior
The nb_dst_host should be at 1, this results in mistakes during distances calculations, false positives and negatives can occur easily

Additional context
This results in the preprocessing algorithm not caching/searching destination IPs during aggregation (as done properly with the ports).
As such, the anomaly filter is not impacted by this bug.