Dedup fix
Fixes the bug mentioned in !24 (merged) (https://gitlab.torproject.org/tpo/anti-censorship/lox-rs/-/merge_requests/24#note_2938727) caused by a problem with serialize/deserialize in the dedeup filters for seen tokens.
Fixes the bug mentioned in !24 (merged) (https://gitlab.torproject.org/tpo/anti-censorship/lox-rs/-/merge_requests/24#note_2938727) caused by a problem with serialize/deserialize in the dedeup filters for seen tokens.