[Fix] Forget old ANN when max_usages is reached to avoid overtrain
[Fix] Forget old ANN when max_usages is reached to avoid overtrain

AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd