[Rspamd] Reduce Sorbs recent score

[Rspamd] Add annoying CSA to bulk symbols and score then with 3.2
[Rspamd] Update to 2.4

data/conf/rspamd/local.d/multimap.conf

@@ -25,6 +25,14 @@ WHITELISTED_FWD_HOST {
   symbols_set = ["WHITELISTED_FWD_HOST"];
 }
 
+BULK_HEADER {
+  type = "content";
+  map = "$LOCAL_CONFDIR/custom/bulk_header.map";
+  filter = "headers"
+  regexp = true;
+  symbols_set = ["BULK_HEADER"];
+}
+
 LOCAL_BL_ASN {
   require_symbols = "!MAILCOW_WHITE";
   type = "asn";